Vibration - failed motor mount?

[Joseph Vanzeipel]

Ok, well I was driving home yesterday (a 9 hour drive) from my brother's
graduation.  I was behind a slow moving pickup with motorcycles in the bed
and the oportunity to pass comes.  Of course, I take it, but when I hammer
it in 4th, the engine (and it seems the whole car) starts to shake, rattle,
and roll.  I shift into 5th after the pass and get off the gas, which causes
the vibration to go away, that is until I have to cruise at around 2500
rpms, which has a bit of a vibration.  After a few hours of this, I have
indentified a few symptoms:
- its worse at rpms below 2000 (really bad when starting from a stop)
- seems to go away under deceleration
- is there when idling (and kinda bumpy too)
- worse with heavy acceleration
- decresed MPG (from CPU indicated 23 to 20, highway driving)

At first I thought a vacuum hose broke loose and alowed dirty (and/or
unmetered) air into the intake system, because it was so sudden.  Now, I'm
pretty sure that it's an engine mount due to the symptoms above.  I've never
been in a car with a busted mount, so is this what I should expect?  About
fixing it:  how much?  I don't have a hoist or access to one, so I am going
to have to make my mechanic a little richer, but by how much?

Thanks,
Joseph Vanzeipel
200q20v - 122k