My uncle has a '98 175 Pro Team Bass Tracker.  It has a 40 horse tracker motor.  It has been garage kept and owned by an older man who bought it new.  It looks brand new, everything works.  

We plan on doing a lot of fishing out of it and to get started into fishing tournys.  

He told a friend of mine that $4700 would buy it. Is that a good deal and would this boat meet the needs of an 18yo wanting to get into tourny(team and single) fishing?

The boat would definitely meet your needs, although the boat is a little underpowered for tourneys.  Since the condition of the engine is the great determiner of the value of the boat, that is one area you want to check out thoroughly.  Try to find out how often the boat was on the water.  If it was used, say the times a week from the day it was bought, then the engine may be due for a major overhaul.  Assuming the boat owner was a casual user, then I would say the asking price is more than fair.

Ok the boat runs good according to my uncle and he wouldnt lie to me.  It was owned by a 76yo man(origional buyer) who didnt take it out much(why he sold it to my uncle).