American Watchmakers - Clockmakers Institute. AWI.
The Swiss Watch Industry-Watch Links. Links to 120 official swiss watch makers websites. Be forewarned--some of the webmasters got carried away and have all kinds of fancy "stuff" on these pages, especially "flash". I don't know who they are trying to impress--- we find it irritating since we don't go to a website to be dazzled by the webmaster's technical knowledge.
Watch It.nl. Watch It! is a Dutch site (in English) which offers a number of articles on a variety of subjects, all related to watches and watch collecting. As you have probably noticed by now, information on the internet about collecting watches is difficult to find.
Horology-The Index. Index and crosslinks to horological information.
Google group: alt.horology. Message board. Ask or answer a question or just "lurk" and read. You must register at this "google" site to "post".
National Association of Watch and Clock Collectors.NAWCC.
British Horological Institute. Lots of useful information here from the UK.
Pocket Watch discussion forum. I believe there is also a wrist watch discussion forum here.