Here is a really good place to start: http://www.hyperkitten.com/
The earlier Stanleys used a higher grade of steel for the bodies. Some even say the blade material was a better grade.
I avoid anything in the “Handyman” series, ones with blue paint instead of black, and ones made in England. In my experience they are a lesser quality than the true Stanley Bailey. I have a couple of #4s (both from the 1940’s) and a #3 (from the 1930’s) that I use on a regular basis.
Just be careful, buying and restoring old tools can be highly addictive. I hear there are a couple of 12 step programs for that, but I don’t have a problem so I don’t know (seriously, I don’t have a problem, I can stop buying them anytime I want. Really, I can…….)
Artisan Woodworks of Texas- www.awwtx.com