www.u2sound.com
Everything you never wanted to know about U2's equipment.
IMHO, if you're just starting out, here's the equipment you want:
1. A Stratocaster with single coils. Preferably Mexican or American made.
2. Herdim guitar picks. The blue ones with the dimpled grip. Go buy them on the web. Hold the pick sideways or upside-down so that you're hitting the strings with the dimples. (If you can't find Herdims, any other dimpled guitar pick will probably do, but these are the ones the Edge uses. And hey, they're guitar picks. They're cheap.)
3. Some kind of tube amp. It doesn't need to be big.
4. Some delay pedal. You can go for the $1000 rack-mounted delay unit once you're raking in the dough on tour.
5. Some overdrive pedal. Edge uses the Ibanez TS-9 most of the time nowadays, but you can use a different one if you like.
If you have enough money for another guitar, then get a Les Paul or some other humbucker-equipped guitar. I say go with the Strat first because it's more versatile. For example, Edge has played songs like "Pride" and "The Fly" with both Les Pauls and Strats, whereas songs like "Streets" and "Bad" and "All I Want Is You" just don't work with a Les Paul.