if you're doing aircraft you can get them on www.greatmodels.com, just do a search for 'color of eagles' and you will find them. As far as true vallejo you'll probably be ok with that ebay store, it's one of the few places online I can find them...
Good luck! Once you get used to them I think you'll LOVe them! I've been using the aircraft colors for about a year now and have slowly replaced almost my entire collection of acrylics with them!