Front brake rotors are the most likely cause. Determine the cause before replacing parts. Uneven or over-torqueing the lug nuts could be the cause.Extended application of the brakes causing overheating could also cause warpage.Check steering linkage for any play while your there,loose/worn tie-rods may exagerate the vibration.
Why defensive? He asked "what could be the CAUSE" not just merely what parts to slap on it. My aim is to help FIX the problem , not just temporarily cover it up. Age of car has very little to do with quality repairs.My wifes' 1995 Camry has 287,000 miles on it now with the front rotors last replaced @203,000 in August of 2004 (toyota pads and rotors at same time). No vibration or squeal yet.Driving habits may also be an underlying CAUSE.