I use Lee carbide 4 die sets that include the factory crimp die. They are the least expensive dies out there and produce quality ammo.
I would ditto the comments about loaded cowboy ammo from those companies mentioned perhaps initially.
The wife and I started with Remington 12 ga. game loads way back when and saved all the hulls. If you do buy some loaded cartridges, save your brass for later when you do reload.
You'll have a bunch of research to do starting out. It's a fun hobby and there's something for everyone.