Well, today while i was driving and all of a sudden my temp guage pinned @ max and smoke started coming out. seems that my rad fluid was empty (even tho i filled it yesterday morning), and i noticed that my cooling fan wasn't turning. I'm assuming there's a problem with cooling fan. Usually how much do those go for @ GM or Crappy Tire or something? any ideas what else could cause this?
Sounds to me like you have 2 problems....
1. Fan not coming on when it's supposed to
2. Where did all the water/coolant go?
Honestly, I'd be more concerned about #2....and worry about cooling the water (the fan problem) after you've convinced the water/coolant to stay in the radiator and engine. If you just filled it, and it's empty or near empty now, where did it go? Look for leaks around the obvious places (hoses, radiator, water pump, etc.). If you can't find any leaks, examine your engine oil....is it milky white/grey? Is there an excessive amount of white smoke coming out of your exhaust pipe? These would be indications of a blown head gasket or an internal leak.
Once you've gotten the water/coolant to stay put, then you can focus on the fan issue...if there is one.
Most likely the fan itself is ok. I would start by checking the fuse, relay, and wiring harness.
Good luck.
-Ferrite