Thought I'd post the practical websites that I found over the years.
For all your American, Japanese & European G1 needs!!!
Some contain more than just G1...
Check em out:

Wiki
tfwiki

Complete G1-G2 Toy Checklist

Toys & Parts archives:
Cobra Island
TFW2005 resources
TFU

Parts and Figure Identification:
Transformerland

Toy Reviews:
Cliffbee

Box Art:
Botch's Box Art

Tech Specs:
TFW2005's Tech Specs
Botch's Tech Specs

Instructions:
Botch's Instructions
Index of /instruction

Toy Catalogs:
Toy Catalog Lists

Original 80s Prices:
The Vintage Space Toaster

Variants:
Fred's Transformers Variants

KO & Reissue IDs:
Highendtfs G1 Counterfeit/KO & Reissue ID Guide
http://www.tfw2005.com/boards/trans...ell-new-ko-reissues-apart-authentic-toys.html

Paperwork Storage and Display Setup:
Paperwork Setup

G1 Online Toy Stores (Not all are verified)
G1s on eBay
Transformerland
TFW2005's Junkion Exchange
Big Bad Toy Store's G1s
TFSource
Robot Kingdom's G1s
TFieds
Brian's Toys

Feel free to add your own in this thread  

 

I cant post links on my blackberry, but Google "fred's transformers variants", its a great site.

 

Botch the Crab is awesome, I've been using his site for reference for years.

 

Thanks turbo!
Fred's Complete Transformers Variants and Variations Page! has been added to the fist post  

 

Yeah, I really love his clean-cut Box Art!

 

I use our Resources before I go anywhere else.

 

Beat me to it! Don't forget all the hard work our on guys here have put into the awesome Resources site!

 

Just added it as the first one on the list  

 

you should link to our Tech Spec gallery too  

 

Done!  

 

Another instructions site is now off-line sadly, but if you go here:
Internet Archive
and type in the site: tfracetrack.com you can find archives of that site and its multitude of instructions. I've been still using it that way, but I guess I'll give the Botch site a try. Bizarrely, I've never come across it before, so thanks!

 

every cobra island toys bot has instructions and tech specs as well as the parts and bots identification, after here it's my next stop for info

 

I can't wait for the day we get all the holes plugged so we're the same way. It'd be nice to have a one-stop shop for all your typical information.

 

You're welcome.
You also have this site for instructions:
Index of /instruction

 

Yeah! Got the link from you  

 

This would be the ultimate place for all that info.

 

Transformers-Toys-Action Figures-Store-Pictures-News for IDing parts.

 

Beat me to it, Optimist! I just realized that transformerland was not on the list and came back to add it since it's quite useful as well. In fact, is there another site to ID parts using colors and such?

 

Good one!
Added  
Thanks!

 

How about this one, G1?

TFArchive - Transformers comics, cartoons, toys and everything else! - Transformers News & Site Updates

It boasts one of the most complete TF comics databases around.

And there's always the tfwiki, of course.