
This is a tricky situation; if the previous owner didn't inform
the dealer of the odometer change, then the previous owner committed
fraud, and he may be liable. The dealer may also be liable; If the
previous owner notified the dealer, or if the previous owner had the 
dash replaced at a dealer, or if the previous owner had the dash changed 
legally, any records search on the car should turn up the fact that
the odometer had been altered.  If a dealer changes the speedometer, he has
to report it (it goes into the car's service record with the manufacturer,
and on the title, if I remember correctly; the dealer told me that
the old mileage, etc. were sent to Ford when my T-Bird's speedo 
was replaced). If the odometer can be set to the old mileage, it must 
be; if it can't (eg, electrically-driven odometers) then the mileage 
of the old odometer must be written on a permanent sticker which is 
affixed to the door frame of the vehicle. 

Either way, if the change had been done legally, then a records search
(which the dealer almost certainly did) should have turned it up.

Call your state's Department of Transportation/Public Safety/Motor
Vehicles--or your tag agent--to find out for certain what your
rights are. Your state's Attorney General will know for certain ;-)

				James