All that Darin said is true. I'd just add that you need to be careful with used CT-20 turbos (the stock turbo on the 22RTE), as their exhaust housings like to crack near the wastegate, and once they crack they become expensive ($600 - $900+) to fix.

Also, if I were going to do a swap, I don't think I'd use a 3RZ; a nice enough motor for a 4 cylinder, but not enough bang for the buck (and I speak from experience, as I have one on my '98 4Runner). 7MGE, 7MGTE and 5VZE are all better choices in the Toyota family, and of course there are other options outside of the Toyota family.

If you want to do a turbo swap the right way, you need some sort of adequate budget. Starting with a low compression 22RE and adding a cheap log-style turbo manifold, a Super-series T3 turbo, a full 3" exhaust, some larger injectors, and a MegaSquirt ECU would position you nicely for 180+ reliable rear wheel horsepower. Remember, adding boost is the easy part, the hard part is building a motor and associated components that will stand up to that kind of power. I speak from experience when I say it's harder than it seems.

-Jeff