I have a 2003 Hyundai Santa Fe, lately everytime i fill up it takes a long while to get it started again.Once it's started, it's fine until the next fill up. any suggestions??

Sounds like the purge control valve on your evaporative system is stuck open. In this case, what happens during fill-up is that fuel vapors are forced from the fuel tank into the intake manifold, effectively flooding the engine.
Todays fuel tanks are vented back into the engine. A "Carbon Canister" is supposed to absorb the vapors and then feed them into the engine in a controlled manner. If your canister is saturated or the purge valve stuck open, the fumes can "flood" the engine while refueling. Try holding the throttle wide open when you start after refueling to clear the vapor quickly.

Also next time you go to fill up, don't fill it all the way, maybe half or so, since the evap lines are at the top of the tank this should solve your problem, and give you at least some good information to take to your mechanic