New to pocket watch collecting? Here is a fantastic tutorial regarding the mechanics of a watch, complete with video:
https://americantimekeeper.com/tutorials

 

Pocket Watch 101 is also a fantastic source for those new to pocket watches, as it contains a plethora of well-organized information:
http://www.pocketwatchrepair.com/how-to/how-to-main.php

A remarkable tool to research most American pocket watches:
https://pocketwatchdatabase.com
(Please note that due to the extensive database here, some of the information is extrapolated from things that are known but have not been directly observed.  Always verify your information.)

An incredible tool for wristwatch research, as well as historical information:
http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&2&2uswk

Antiquarian Horological Society, with extensive research on the art and history of time measurement:
http://www.ahsoc.org

Since 1858, the British Horological Institute has been a source of news, education and more:
http://bhi.co.uk

NAWCC, a community of watch and clock collectors with extensive records, research, education, venues for information exchange, etc:
https://nawcc.org

Hodinkee, a robust online magazine featuring in-depth reviews, critiques, and reports on watches of particularly high quality:
https://www.hodinkee.com

Worn and Wound, for news and blogs on value-driven watches, the most beautifully-designed and well-crafted timepieces, regardless of price point:
https://wornandwound.com

Watches by SJX, Asia's leading journal dedicated to fine watchmaking, covering mainly wristwatches but with some focus on pocket watches:
https://watchesbysjx.com

Revolution Watch Magazine celebrates the craft, culture and joy of watches and watchmaking through a dozen international editions and its website:
https://www.revolution.watch

The most complete source for Seth Thomas information out there:
https://seththomasresearch.com

A must-visit for Hamilton collectors:
http://hamilton.rrstd.com/Hamilton/Hamilton_Home.html

Resource for all things Elgin:
http://elginwatches.org

A guide to Illinois Watch Co. size 12 watches:
http://www.illinoiswatchguide.com

Exhaustive resource on Glashütte watchmaking: 
https://www.glashuetteuhren.de

Excellent research tool for Bulova wristwatches: 
https://www.watchophilia.com

The Americal Watch & Clock Museum:
http://www.clockandwatchmuseum.org

 

 

Digital image library of English table clock engravings, wonderful for authenticating these clocks:

 

Great resource for watch parts and tools - just email Dave to see if he has what you need:

 

 

 

Location of LIVE auctions at The Hilton Doubletree Manchester Downtown Hotel (formerly Radisson)
https://doubletree3.hilton.com/en/index.html