really can't get to the clutch. The rear main seal is a $17 part that should've been replaced at the same time your clutch was. Maybe your clutch mechanic is trying to gloss over that issue, but I hate to cast aspersions.
Other considerations : simple clutch adjustment (at the pedal) might fix things, look in the FAQ. Maybe your clutch is already fried (for whatever reason) and has nothing to do with your oil leak.