The other problem that you run into is the length of the slip yoke in the transfer case. You can switch it to a YJ yoke which is longer but there goes some more $$. 2" will usually not cause any vibes and like said above, a 1" x-fer case drop can fix that and usually be found fairly cheap. If only going 2" or so, I would just make it as affordable as possible and go the budget route. Save the real mod money for when you get inchitis and end up going for 4.5" and 33's then you will need the $$.
I have aquired all the parts to do a 3" lift on the XJ of my sons friend. Almost all of it was donated.
I have 2" add a leaf rear springs - free
front rancho or sj 3" coils - free
discos - free
ZJ steering - free
transfer case drop - $7
front rustys tow hooks - free
rear 1.5 - 2" shackles - $50-ish
steel KJ rims - free
245/75 MT/R's - free
More to come as we find it. Now if he could just stop having other problems long enough to get the dang lift installed....
My point is that you can find good deals or freebies if you get in good w/ a local club or forum such as NAXJA and beg, borrow and barter for stuff. There is also a wealth of info on NAXJA for XJ's. Please come back here and share what you learn though so we can grow this section here too.