engine "tapping" noise on start up

I have a 2005 tribute.  Love it!  I noticed recently that on start up there is a tapping noise coming from the passenger side of the engine and usually goes away when the car has been running for a few minutes.  Does anyone have any ideas?  I REALLY do NOT want to take it in to the dealer.......!!!!!  Any help would be appreciated.  (and, yes, the oil dip stick reads full)
Thanks!

The noise may simply be just the belt or on a more serious note their is a tsb for some of the 3.0 the front cylinder head cam shafts were not torqued right and the caps need to be removed and re torqued in a special sequence. I recommend taking it to a reputable shop and figure it out. Any good shop should have access to these tsbs.