Backyardmetalcasting.com This site is loaded with burner, furnace and general casting info
theworkshop.ca This guy casts using lost foam, he has lots of photos and gives plenty of detail, this is my personal favorite casting site
Mr. Reil's Home Page A wealth of great info, famous for his burner designs.
Zoeller Forge He's got Forge info and a small propane supply store. He also sells premade burner flares for the Reil burner. I plan on buying from him, I'll get back on how satisfactory the buying experience was.
BuildYourIdea.com Lots of great foundry and CNC information, I know, I say all of these sites have great foundry info, maybe it loses some of it's credibility in your eyes every time I say it, but trust me that I only put up sites that have great foundry info, in fact, it's becoming a little redundant to say it then, I mean, why would a I put a site with very little info up in the first place, but I digress, make sure when you go to this site you check out the Home Brew Linear Bearings section under CNC, it's amazing, it shows some great talent with the CNC as well as the best finish I have seen using a hobby foundry
Foundry Home This site...a few teens try to cast metal.
Foundry and AMC Home Home