I just bought a 98 Silverado 1500, and would like to lift it a little. Just 2" - 3" should be fine. Do those small kits I can buy on eBay work?

And would I be able to put a good size tire on once I do this lift? Can I keep my existing wheels?

As you may notice, I am on a tight budget...!

 

If you're on a tight budget, and you only want 2-3" of lift, then a body lift is the way to go. Now, keep in mind, you will be able to fit larger tires, but that will be the only advantage you gain when considering offroading. If you intend on lifting it for offroad capability, then, for one, 3" isn't going to do much, and two, a body lift would be pointless. But, that's really beside the point. You should be able to use the same wheels; I believe you can get up to 37" tires for 16" rims, though I don't know what size your rims are.

Here's a kit I found, quick search, no real research done: Lift