Micromark is a great place for great tools. Don't forget to give places like Hobby Lobby and even Ace Hardware a try as well. Several of my modeling tools came from the $3.99 bin at Ace, the Dollar Days bin in WalMart and the Artist's supply section at Hobby Lobby. I've found that the humble single edge razor, retractable knife and those disposable snap blade knives are quite adequate for most heavy cutting found in modeling.