Lose Of Compression

I was recently told that I have no compression in one of my cyliders of my 99 SC2 and more diagnostic work would be needed. Mind you I had already paid for one dianostic and a procedure and that wsn't the problem.

Give me some clues on what could be the problem?

P.S. I am a woman and don't wish to be taken by anyone. Any of you Saturn gurus taht may know a few things please give me some suggestions.