I bought a new car last spring and when I looked at my credit report the other day it showed over 15 inquiries at that time. My car dealer said they were 'shopping it around to get me the best deal' which is great except for now I have all these inquiries...

Does this hurt and is there anything I can do about it? How long will they stay on there (been over 6 months)?

They will remain for 2 years. If I was you, I'd dispute them! I wouldn't let the dealer's "shopping" hamper your ability to get credit. They should have given you some type of agreement to sign before they could just start plucking your credit report left and right! If they don't delete the inquiries, contact the CRA's and dispute that way. STOP AT NOTHING! Persistance pays off! Good luck!