I compiled the list from Frank and mine. I can't vouch for all of these and I have no idea if Frank can on his side. Anyway, cut n paste the address into a new window or tab! Some of these, you'll be familiar with, others not.

Hasbro Toy Shop.
www.hasbrotoyshop.com/

Small Joes
www.smalljoes.com

JoeHQ
www.gijoehq.com/catalog/

Killer Toys
www.anime-killertoys.com/

Big Bad Toy Store
www.bigbadtoystore.com/bbts/default.aspx

Guru Planet
www.guru-planet.com/

The Collector’s Depot
www.store.bullmarkettoys.com/gi-joe---3-75-.html

Brian’s Toys
www.brianstoys.com/store/Default.aspx

D&S Toys
www.dnstoys.com/

Joe Armory
www.joearmory.com

Reil Toys.com
www.reiltoys.com

GI Joe Heaven
www.gijoeheaven.com

Good Stuff To Go
www.goodstufftogo.net

Digital Toys
www.digital-toys.com

Back In The Day Toys
www.backinthedaytoys.com/bitdt.htm

Weapons For 1/18th figures.
www.marauderinc.com

Empire Island (for those in the UK)
www.empireislanduk.com/store...HasbroFront.htm

For stickers…
www.reprolabels.com

To look up bio cards, figures parts, vehicles, the latest news and more…

www.yojoe.com
www.joebattlelines.com
www.joesightings.com
www.toynewsi.com
www.gijoe.com
www.joebattlelines.com/m6d/index.html
www.joebattlelines.com/s6c/index.htm

Auction sites
www.ebay.com

Dio parts:
www.build-a-rama.com

Other peoples custom figures, dios, file repository, etc;
www.joecustoms.com
http://wiki.joecustoms.com/wiki/Cat...File_Repository
http://gijoe.lukeellison.com/
http://violentfix.com/cobra/
http://www.loserville.us/~truegrittcustoms/
http://www.loserville.us/~gunslingercbr/
http://www.myuselessknowledge.com/joe/gihome2.html