Bug1,
1. In addition to the gaskets listed by Lucas5477 you may want to purchase the following also; turbo to exhaust manifold gasket, turbo oil drain gasket. If your valve cover gaskets are not leaking I wouldn't replace them as they are easy to do later.
2. Replace the rubber portion of the fuel supply and return lines while you have the head off; MUCH easier! Replace the fuel filter also. Clean the fuel strainer.
3. Radiator hoses, heater hoses, bypass hose, trans oil cooler hoses (if you have an auto) and of course new stainless steel clamps all around.
4. Have the radiator pressure tested and boiled clean. New anti-freeze and rad cap.
5. Good time to install new upgrade injectors or have old injectors tested and reset.
6. Mark the harmonic balancer for Top Dead Center while you have the head off.
Trent