I use one of the cheapest drill presses you can get (same model sold by
Grizzly and
Harbor Freight), and it's seriously been fine. One advantage of it not being super powerful is that if an enclosure snags, you can hold it with your hands... With more powerful drills, you'll want to clamp it. I nearly broke my hand with one when I was just starting out. No such problems since getting the smaller one, though.
I use step bits, personally. I use a big one for jacks and such, and a smaller one for the faces of the pedals. They're shorter than typical drill bits once you get to the bigger sizes, so they fit little drill presses better. But you can get shorter drill bits (though, I had trouble finding them).
There's a step bit that goes from 1/8" to 1/2" in 1/32" increments. That's the perfect range for pedals, and I think they're a pretty standard size. The larger one I use goes from 1/4" to 3/4" (I think) in 1/16" increments... it doesn't cut as clean, but it makes big holes go quicker. It's more likely to snag, though.
One thing I can't stress enough: Cutting fluid. I've had basically no problems with snags since getting this stuff. Even with the drill set to high speeds. And I've been using the same step bits for like a year. They gum up pretty quick otherwise (though, you can chip off the gummed on aluminum with a screwdriver).