As you've already noticed, now is NOT a good time to buy mags. I have the Glock single pistol range bag -- LGS tossed it in when I bought my G30. But I can't compare it with anything since it's the only one I have. I wish it had a little more room, though. With four mags, a handgun, and a couple hundred rounds of ammo, it's tough to get the zipper closed.
Good on you for requesting an owner's manual. Here's
the "preventive maintenance" section of the manual from the Glock website. Notice that Glock doesn't recommend any particular brand of gun solvent or lubricant. Any name brand should work fine.
First firearm, eh? You're in for some fun
Again, welcome aboard!