Hopefully a UK specific thread will be of more assistance on its own, for UK residents.
I posted previously in the general libraries thread but felt that it was only going to get lost in amongst the much larger US and Canadian collections so thought I'd post here in a UK specific thread.
Although at the time of the original post numbers are low, its early days yet for the UK and digital downloads. Theres some catching up for UK libraries to do. Here is a list of the current collections and addresses for those that I know of.
I've only listed ebooks, and not the audio-books.
Manchester UK
http://manchesterdownload.lib.overdrive.com/
Ebooks
Fiction 967
Non-fiction 600
London libraries consortium
http://llc.lib.overdrive.com/
Ebooks
Fiction 926
Non-fiction 503
Essex
http://essex.bookaisle.com/
Ebooks
Fiction 485
Non-fiction 342
Liverpool
http://liverpool.lib.overdrive.com/
Ebooks
Fiction 623
Non-fiction 209
Oldham
http://oldham.lib.overdrive.com/
Fiction 182
Non-fiction 41
York
http://yorklibraries.lib.overdrive.com/
Ebooks
Fiction 138
Non-fiction 42
Surrey
http://surreycc.lib.overdrive.com
Ebooks
Fiction 264
Non-fiction 185
Derby
http://derbycity.lib.overdrive.com/
Fiction 1470
Non-fiction 355
Herts
http://herts.lib.overdrive.com
Fiction 441
Non-fiction 165
Aberdeenshire
http://aberdeenshirelibraries.lib.overdrive.com/
Fiction 620
Non-fiction 77
Norfolk
http://digitallibrary.norfolk.gov.uk/
Fiction 1509
Non-fiction 528
Here is a list of joining requirements (where known);
Liverpool - allow you to join on-line. States that they will send membership card to you in the post, but you then have to call into any Liverpool branch to have card authorised.
London - allow you to join on-line, but you have to collect your library card from a London library. Proof of UK ID required at time of Pick-up.
Manchester - allow you to join on-line but you have to collect your library card from a Manchester library. Utility letter required to prove your address (anywhere in the UK allowed)
Surrey - allow you to join on-line as an elibrary member, will email you a virtual library card. Anyone in the UK can join.
Essex - allow you to join on-line. Emails you a membership number immediately upon application. Anyone in the UK can join.
Oldham (near Greater Manchester) Joining criteria unclear from website.
Derby Local residents can join on-line. Work, study or visit can join at branch.
Herts On-line application.
Aberdeenshire Take proof of your name and address, such as a driving licence or utilities bill to one of our libraries and complete a registration form.
Norfolk Need to be based in area to join (work, live or study).
Warwickshire Need to be based in the area to join (work, live or study)
Wokingham Not an Over-drive service. Stock unknown. See site for details.
For some reason I don't understand UK libraries don't make much of a fuss when they start their digital libraries so its easy to miss new additions. If anyone else knows of any others then please reply to this thread as and when you find them.
There is a VERY good forum specific Wiki page
HERE many thanks to pdurrant for taking the time to both add these contact details and point this out.