i have my timing belt already...what other belts do i need to change when i get my timing belt done? its a 98 civic ex

 

If they have never been replaced, you may also want to replace all three drive belts (PS, A/C, alternator).

Consider also replacing the timing belt tensioner and water pump, as well as the valve cover gasket, spark plug seals, and valve cover bolt seals. Another item to consider is checking the valve clearance.