Main databases:

Berg Fashion e-books (210+ titles)
Dress and Costume Library e-books (68 titles)

Cambridge Companions

Cambridge Companions to Literature & the Classics (416 titles)
Cambridge Companions to Music (81 titles)
Cambridge Companions to Philosophy, Religion & Culture (237 titles)

Drama Online - Critical Studies (349 titles)

Drama Online - Theatre Craft (143 titles)

EBSCOhost e-book collection (5 titles)

African theatre 9: histories 1850-1950
Applied theatre: bewilderment and beyond
Fundamentals of theatrical design … scenic, costume and lighting design
Great lengths: seven works of Marathon Theatre
Performing new lives: prison theatre

EBSCOhost e-Classics collection (23 titles)

EBSCOhost IBTD e-book publications (558 titles)

EPDF  
Download free pdfs for a large variety of books e.g. Fortier's theory/theatre, Cambridge companion series, Routledge companion series, Cambridge Opera Classics etc.

Google Books (Internet - free)
The full-text online of a growing number of books, and previews of thousands more.

GooglePlay (22 titles) (ask College Librarian for access)

An actress prepares / Rosemary Malague
Beyond scenography / Rebecca Hann
The complete conductor's guide to Laban movement theory / Lisa Billingham
Digital media projection design and technology for theatre / Alex Oliszewski
Dionysus in exile: the theatre of Theodoros Terzopoulos / Gerald Muller
Gaslight / Patrick Hamilton
Get real: documentary theatre past and present / Alison Forsyth and Chris Megson
Her turn on stage / Grace Barnes
Intimacy in cinema / David Roche
Julius Caesar [Shakespeare in Performance] / Andrew James Hartley
New Finnish theatre / Jeff Johnson
New visions in performance: the impact of digital technologies / Gavin Carver
Piscator notebook / Judith Malina
Postdramatic theatre and the real / Michael Shane Boyle
Psychophysical acting / Philip Zarrilli
Routledge companion to Jacques Lecoq / Mark Evans
Skating on air / Keli Lawrence
Theatre of movement and gesture / Jacques Lecoq
Theatre of the real / Carol Martin
Theatre, performance and technology / Christopher Baugh
Thinking through theatre and performance / Maaike Bleeker
To the actor / Michael Chekhov

Internet Archive
Create a free account, and then log in and borrow books online.  

JSTOR Open Access e-books (6,000 titles, c.4700 in English) 

Open Access (oapen) (50 titles in Theatre Studies)
Open Access general index of subjects - a quality controlled collection of open access books.
Includes titles in French, Italian, German, Dutch, Norwegian etc,

Open Research Library
Covers a wide range of subjects. Many of the titles within Drama and within the Performing Arts are listed in the excel spreadsheet.

Palgrave Macmillan e-books (12 titles) (ask College Librarian about these titles)

After in-yer-face theatre
Animation, embodiment and digital media
Contemporary approaches to adaptation
Debbie Tucker Green: critical approaches
Digital bodies
Experimental and expanded animation
Handbook to women on stage
Immersive embodiment
New media dramaturgy
Reframing immersive theatre
Theatre, social media and meaning making
Video games and storytelling

ProjectMuse Open Access (87 titles in Theatre and Performing arts)

Theatre and Drama Premium (209 titles)
Amongst all of the plays, videos and theatrical memorabilia, there are some 209 full-text books and these include many titles used frequently on DMTA courses.

Unbound (3 texts)

Vanishing Points - PDF
Ways of Getting Classy: A Toolkit of methodologies - PDF
Performing Research: A Toolkit of Methodologies - PDF

VitalSource bookshelf  (8 titles) (ask College Librarian for username and password)

Contemporary ensemble: interview with theatre-makers
Gardzienice: Polish theatre in transition / Paul Allain
Hidden territories: the theatre of Gardzienice
Screens producing and media operations
QLab 4 show control
Automated performer flying
Stage manager's toolkit
Teaching with confidence in higher education

Open Access:

Bloomsbury Open Access
Covers subjects such as Anthropology, Film and Media Studies, Politics and International Relations, History, and Education.

Bristol University Press & Policy Press: Open Access
Predominantly a social science publisher, but there may be titles amongst their Business & Management or Sociology offerings that could be useful.

Humanities Digital Library
The Humanities Digital Library is the open access library and catalogue for books published by the School of Advanced Study, University of London.

Project Muse: Open Access e-books
Project MUSE offers open access (OA) books and journals from several distinguished university presses and scholarly societies.

University of California E-Book Collection
On the left-hand side click on the link to Browse Public Titles.

University of Michigan Press: Open Access
University of Michigan Press publishes books and digital projects in the humanities and social sciences including the performing arts.This links to the open access collection.

Ukraine books
A husband and wife who have/had a small publishing house in Kyiv, since they can no longer publish paper books, have decided to distribute them FOR FREE in electronic form. You can download the books Interesting Ukraine, Interesting Kyiv and Interesting Chernobyl as PDF files. Although the books are free, you can make a donation towards them if you wish.

Historic Books:

JISC Historic Books
JISC Historic Books contains the full text or page images of over 350,000 books published in Britain from 1475 to 1900. The service draws together content from EEBO (Early English Books Online), ECCO (Eighteenth Century Collections Online) and a digital collection of more than 65,000 first editions from Nineteenth Century Books covering philosophy, history, poetry and literature.

Proquest Early European Books
Early European Books traces the history of printing in Europe from its origins through to the close of the seventeenth century, offering full-colour, high-resolution facsimile images of rare and hard-to-access printed sources

Bexley Libraries:

Oxford Reference Online (Bexley Libraries)
You are entitled to access this as a member of Bexley Libraries. 
Use the log on via your Library card number.

Oxford Dictionary of National Bibliography (Bexley Libraries)
You are entitled to access this as a member of Bexley Libraries.
Use the log on via your Library card number.

Oxford Reference Online - Performing Arts (Bexley Libraries)
As a member of Bexley libraries who can have access to Oxford Reference Online.
The Performing Arts section includes the following:
The Oxford Companion to American Theatre
The Oxford Dictionary of Dance
The Oxford Companion to Shakespeare
The Concise Oxford Companion to the Theatre
Use the log on via Library card number.

Multidisciplinary collections: drama and literature

ALEX Catalogue of Electronic Texts
Main focus is on American and English literature and Western philosophy. 

Bibliomania: Free Online Literature and Study Guides
Thousands of e-books, poems, articles, short stories and plays.

First World War Poetry Digital Archive 
An online repository of over 7000 items of text, images, audio, and video for teaching, learning, and research.

Internet Archive: Texts
Access to historical collections that exist in digital format.

ManyBooks.net
Access to some 25,534 eBooks.

Online Books Page
A listing of over 35,000 free books on the Web.

Online Library of Liberty
Electronic versions of classic books about individual liberty. There are separate sections for Music and for Opera. Although there are not many titles, what there is may be useful.

Oxford Text Archive
High-quality digital resources for research and teaching.

Perseus Digital Library
The main collection covers the history, literature and culture of the Greco-Roman world, but there are other collections e.g. the Renaissance, and 19th century American sources.

Project Gutenberg
The first producer of e-books, multi-disciplinary in scope.

Rare Book Room
An educational site intended to allow the visitor to examine and "read" some of the great books of the world. The texts are not solely literary: e.g. there are samples of written music from Beethoven and Mozart.

WWW Virtual Library
Texts and plays online

Miscellaneous:

Arts Council of England: Research and data

The Audience Agency
Although primarily an agency to help cultural organisations analyse their audiences, the Insight section does provide a variety of report on audience demographics.

Creative Blueprint
Downloadable research publications from Creative & Cultural Skills and other organisations with an interest in the creative and cultural industries.

Creative Industries
Publications from Creative UK, an independent network for the UK's creative industries.

Equity Documents
Reports and documents produced by Equity, the Actor's Union.