As has been said by a couple other folks, plug kits are the way to go. I had a hole in the tread of my car a couple of months ago and the cheapest plug kit Walmart had to offer had the tire repaired in 15 min for like $10. Plus, I have a bunch of spares for when i inevitably catch another nail.

Don't use the slime shit, it may work, but it makes an enormous mess inside the tire that is going to piss off the next mechanic that takes your tire off.