specifically re: sticking odometer.  If the speedometer is going ok, it is 
not likely that the speedo drive is disconnected.  You will probably find
a little white gear in the odo drive is broken or loose on its shaft.  Espec-
ially in the loose on its shaft case, you may have luck fixing it.  Get some
coarse sandpaper and scrape the shaft to make scratches along it (not around
it).  Put a pinpoint of superglue on the shaft and reassemble.  You may also
want to consider leaving a piece out so the odo drive only turns the full odo,
not the trip.

Noone I've talked to has had much luck in buying the little gear alone.
B.
PS for non-mind-readers: all above assumes that you have taken the instrument
pod out, taken the speedometer of it, and disassembled the speedometer on the
kitchen table.  Make notes as you go unless this is your >3rd time doing it.