Book Worm.

There is a set of books, though it is now rather old, which runs to 2 or 3 volumes. The author has a German surname but I can't for the life of me remember it  I'll do some thinking and see if I can come up with it, though the set may well be too old for what you want. One shop I used that has since closed used them for finding info for customers.

Thank you Richard, that's the one 

I'd get Volume 1 and see how you like it. It's available for very little on EBay used. It also contains a lot of info about fish biology, plants etc., some of the stuff about fishkeeping may seem out of date (it's from 1982) but a lot of it seems to me to be more sensible than some of the more "modern" ideas. It has most of the commonly available fish and a lot that are not readily available (600 fish in total) but of course there are fish common today, such as the Celestial Pearl danio, which weren't discovered or imported until later. These are fat books and so good value used, Volume 1 has 992 pages!
Other books I have are mostly pretty useless, many just repeat the same (often incorrect) information, much like many web sites...............