A few of the people on this forum might not agree with me but i won't change my statement that i'm about to make.
The 30-30 Winchester is about the perfect caliber for 200 yards and in. It'll handle moose, deer, bear and anything else that you want to shoot at. This caliber has killed more animals than you will ever see in your lifetime. Chambered in a Marlin 336 or a Winchester '94, it makes the perfect brush gun. I use a Marlin 336 chambered in 35 Remington or a Savage 99 in 300 Savage but i would not ever tell a guy not to use his trusty 30-30. The only reason i don't use a 30-30 is that i like oddball calibers. It costs more but i like being the guy with the different calibers in camp.
You'll find ammo for it in pretty much any store that sells ammo. It's pretty cheap when you compare it to a 30-06 or 300 mag. (17ish$ a box for 30-30, 25-30$ for 30-06). If you plan to hunt with your rifle, then buying factory loads is not a bad idea. If you plan to use it at the range, then reloading might be your best bet since it's cheaper. Test out your rifle with as many different factory loads that you can find and see which ones are the most accurate. I don't think you'll ever regret buying that gun in that caliber man. Good luck.
Dorian