Free: Contests & Raffles.
It is what you make of it, don't let anyone tell you you need a boat, boat blind, dog, etc. to get into the sport. You can shoot birds with a very minimal setup if hunting sheet water fields, heck you might not even need waders depending on where you hunt. If you get hooked look out, it could get expensive!
deltaops, It's only money and there's no better way to spend it than on hunting/fishing and the kids when they go w/ya.