I have a ton of Winchester White box and I like it. Right now for range ammo I am using the Wolfe Ammo I bought when 45 acp ammo was hard to come by. It is OK but on occasions I have a Fail to Feed. Just gives me a chance to work on my Malfunction drills But I have used S&B in the past with great results also. I shot a 1,000 round Swat Pistol Course put on by LAPD using S&B with 0 problems!
If you're looking just to buy at a local store, look for WInchester WHite Box 100 Bulk Packs and Federal 100 round Bulk Packs.
Next would be stuff like Blazer Brass and PMC Brass.
If you're looking at bulk purchasing, Freedom Munitions has some excellent pricing.
Check out ammoseek.com, plug in your caliber info and it will tell you who has the best pricing. Watch out for places like Cheaper Than Dirt, however. They get you on the shipping. I mean "get" with a capital "RIPOFF".
Welcome to the forum! One thing I see that hasn't been mentioned, Freedom munitions has a brass program. 1lb. of brass = $2.50. Any caliber that they sell. If you go to their page, it is a little more detailed than I am. But basically you can trade in brass almost up to the purchase price, but not exceeding it, to my understandings.
Best of luck, enjoy your G22, and again, welcome to the forums!