Check out Rubicon Express lifts. They can be a little more expesvie than some other kits, but I believe it is well worth it. I have the 3.5" Super Flex kit on my XJ right now and its great, I plan on upgrading to the 5.5" in the spring.
As for other parts you will need. Most kits come fairly complete. You will need a slip yoke eliminator and a new rear drive shaft. The SYE(slip yoke eliminator) will allow for the drive shafts steeper angle, and the new drive shaft will compensate for the longer distance.
SOmetimes you can get away with a transfer case drop, but if you are going to go that big right off the bad you will need a SYE.
Good luck man, keep us updated on how it turns out when you get it
'00 Cherokee Sport / RE 5.5" LA / 33x12.5 BFG KM2's / soft 8's / Yukon 4.56's / Rugged Ridge T link steering / AA SYE with Rocky Mountain Driveline Shaft
'92 YJ sold