this is the first time ive gotten my guitar set up, and the charged me $45, is that a good price, or did i get ripped off?
is it necessary to get your new guitar set up even if it is intonated and I've already restrung it?
I do all my adjustments myself now to save time and money but I have a basic guitar setup...

Once you setup a guitar you don't normally have to do it that much....the most you will need to do is set intonation or adjust the truss rod a few times a year.

When I change strings I check my intonation but the truss rod normally doesn't need any adjustment.