First - pick up as much 9mm as you can. I don' think I've ever paid for 9mm/.40/.45 brass. Plenty of shooters leave it on the ground for free. All you need is a couple hundred to get you going, then your stash will grow as you find more.

If you have to buy brass, get the cheap stuff from Midway, or other sources.

Don't ever buy (or even pick up) military 9mm brass unless you want to waste a lot of time removing primer crimps. You're going to lose some brass, and pick up other brass you find on the ground.

New 9mm brass? No way.
Koski