My dad owns a .22 that just sits in the garage collecting dust. Its an old trainer single shot, and its hella dirty, but I'm sure with a little cleaning and permission, I could take it out to the range and have a little fun with it for cheap.
As for shooting guns, I've actually never shot anything outside of a Glock 19, and I only did about three clips, so I have little shooting experience in general, especially with rifles, which is limited to BB and pellet rifles (I know, that doesnt count).
Huh, might be pretty fun to clean up that old .22 and give it a whirl. Might give you an excuse to store the rifle somewhere safer too. A garage is usually a rust-prone environment, so "Gee Dad, I better keep this in my closet with the bolt stored separately, since I spent hours cleaning it" might be a diplomatic way to get your own gun.
Post back here and let us know what kind of .22 it is. Maybe you'll be lucky at it'll be some awesome vintage target rifle.
I'll leave it to other folks to recommend online reading for shooting instruction, but you would be highly advised to do a little reading up on the basics:
-sight alignment
-sight picture
-breath control
-trigger control
-the myriad positions, etc.
These things would best be learned by actual coaching, but in the absence of money or a free coach, reading up and taking them seriously would be a great start. The great upside of a single-shot boltgun is that you're obliged to take your time with it, so you'll be totally immune to the desire to "spray and pray."
Do bear in mind that every other week the Marine Corps takes a bunch of random (mainly teenage) yahoos out to the snapping-in range for a week to practice the basics with an unloaded rifle, and then maybe four days of shooting with actual live ammo. The result: practically everyone can regularly hit a man-sized target at 500m from the prone. This is purely a result of teaching the basics listed above, and taking them seriously.
I'm totally for getting out and having fun with a gun, but you'll have all the more fun if you know the basic principles and can smoke the CounterStrike kiddies who dropped $900 on an AR they can't shoot. Get in practice with the .22 boltgun, and you'll be ready to turn heads with the AR.
(Reading this post, I think I sound like I'm some cantankerous codger, but I'm actually in my late 20s.)