Well, my compiler is being screwy, so i'll look at it more when i get that running again (damn you VS .NET!) but i noticed for your include your using iostream.h which is the old version, now use:
#include<iostream>
using namespace std;
is the easiest way.
Also, in your .cpp file, you didnt specify any return types, which is probably why your getting all those "overloaded function differs only by return type..." errors.
for example:
int Employee::GetHours()