Whats next?

My A/C went out last evening.  No clue why.  Was working fine then it wouldnt turn on anymore.  I have checked everything and inspected the entire unit.  I will now have to find someone who can come out and look at it to tell me whats wrong.  Thats $50-$100 for the visit, then what ever it will cost.  I will have to try to come up with the money - no idea how.  It is very hot here!