I agree with Darkroot on this one. Most other Adobe software is just as expensive, but also just as worth it. Flash is extremely powerful and is pretty the only way (unless you are a computer whizz enough to outclass Adobe and design your own software, which I doubt) to make Flash (notice how they are the same name as the program) games. And how to make them well is to read a book.
Its a bit obvious, in a way,
GamingAchilles