Parts should just be a belt and tensioner kit - usually thirty to fifty quid for a decent make kit (SKF or Gates) from an independent factor. You can buy belts on their own, but any professional mechanic worth their salt will change the tensioner as well. If you buy the kit is has everything you need, including any replacement bolts or gaskets.
The procedure is fiddly rather than difficult, usually because access to the belt is restricted rather than the task being at all complicated. You will need a good basic toolkit (socket set, pliers, screwdrivers) plus a torque wrench.
Buy a Haynes manual for the car which will list the procedure in detail as it's a bit long to mention here. It will also detail the correct way to tension the new belt, as this varies from engine to engine. It's vital you get this right as getting the tension wrong can cause the new belt to fail or slip. Both bad!
Of course it's something a lady can do! :o)
DP, May 2006
