Jeep Repair: A/C Unit, jeep sport, liter car

Question
I have a 01 Jeep Sport Cherokee 4.0 liter car.  My A/C Unit has just recently stopped blowing cool air.  My questions are;  What can I do myself to possibly resolve the problem before having to take it a shop? How much would I be looking to spend otherwise?

Answer
asking the wrong questions first of all.
IF u dont know whats wrong then cant be given any sorta price range correct? Ask a DR how much its going to cost u to fix yourself and have not even told him whats wrong??  Sounds kinda silly huh? If u dont have any way of doing any tests then u will need to have some one look at it and then u get get what u are asking for.
I live in Atlanta I would take a look at it for u.