Complementary and Alternative medicine Library and Information Service (CAMLIS) this is based at the Royal London Hospital for Integrated Medicine and contains a large collection of CAM books and journals. Anyone is free to visit, read and photocopy, though only members can also access the electronic resources.

British Library can supply copies of almost any article, generally quite quickly, in electronic or paper form. Alternatively it is possible to visit in person and read and copy articles there. Material can be ordered beforehand to ensure it is there when you visit.

Wellcome Library : for historical material on East Asian medicine

Institutional libraries: even if you are no longer affiliated you may be able to get access as an alumnus or through being a student/staff elsewhere, or even sometimes just as a local inhabitant.

Local authority libraries: you can theoretically order anything through inter-library loan but the charge is no longer always negligible and the waiting time is very variable

Cochrane Library you can freely (in the UK and many other countries) search the database of their own (highly regarded) systematic reviews

National Library for Health (formerly National Electronic Library for Health) this was a very useful NHS resource that changed into a rather less useful NHS resource and now has disappeared altogether. The url takes you to a NICE website that provides resources that are largely accessible only to NHS personnel.