what kind of mags are you looking for? cosners has a good amount of pistol mags at fair prices, I was just there about a 1/2 hour ago and picked some 226 and XD mags.
I usually order stuff from Midway because of the C&R discount, but I just ordered 10 30 rd and 10 20 Round AR mags from Brownells. They're their in-house mags so we'll see the quality. I was bumming though, they charge Indiana sales taxs!