It's also at Jo-Ann's and Do-It stores.
It's funny, though. I've had the exact opposite experience -- I've been seriously disappointed with Krylon lately, and have sincerely fallen in love with Rust-Oleum. Also, TLobe, I went with the slightly harder to find Rust-Oleum Cobalt Blue instead of the Royal Blue. Almost the same, but Cobalt seems more... warlike, somehow. *heh*
If you want to go with airbrush colours, I'd suggest spraying the paints listed above on some pieces of cardstock or scrap plastic and taking them in to your nearest hobby shop and comparing to Testors/Floquil/PollyScale/Tamiya/whatever paints to find good matches.
--Jonah