2003 Jetta vr6 antena problems?

I just purchased a 2003 jetta vr6, used. My dad test drove it and said the radio stations were comming in pretty well. But once we got it home the radio stations are blank. if you push seek it will go threw the stations endlessly. ive done little to check i just took the antena off and screwed it back in, and it was no help. im some what scared to mess with the stereo deck with out having any advice. any suggestions?
Thanks