I've got some white smoke and sweet smell and a little bit of oil leak near the back left where the exhaust is...according to what I've read in the forums it is a warped/bad head gasket. I am not qualified enough to fix it. How much should I expect to pay?

between 1000 and 1500 if somebody else does the work. 150 if you do the work.

Why such the disparity? Is it that much labor?

Depends on the shop. IIRC it is like 9-12 hours of labor.

between 1000 and 1500 if somebody else does the work. 150 if you do the work.
i agree-did the work myself 6 yrs ago when the po had the s14 engine rebuilt,kid didn't properly break in the engine and the hg blew,i replaced it costing close to $200 w/ new headbolts and gaskets....
got my parts from maximillians.....