Best options is to buy a kit specifically for the JK. It should include eveything you need. Check out some of the 2.5" kits available on
www.quadratec.com It'll give you an idea of what the come with.
Minimum recommendation would be a spcaer kit, which will include spacers and longer shocks, but not springs. Then you move up to spring kits. ARB have recently announced a 2" lift for the 2-dr JK. Get on to an ARB store/dealer for details.