The first thing you should do is hunt down a good article on overclocking so you don't destroy your PC and then come back asking what the hell happened
. Then, after you have a solid understanding of what overclocking is, read your motherboard's manual.
A 500MHz overclock is modest enough to be practical in most situations, but, you aren't guaranteed to get any kind of an overclock with your CPU. Some can be pushed an extra GHz, some buckle at a measly 200MHz overclock.
You also need to understand how altering the FSB will effect the rest of the buses in the system, and how FSB:RAM ratios work.
That said, most Asus boards (including yours) come with preset overclocking profiles (5%, 10%, 20% and 30% overclocks), so you don't have to overclock the FSB manually, 1MHz at a time. It is advisable (in your situation) to take advantage of these profiles, starting with the 5% and working your way up after the system's stability is ensured.
Enter the BIOS (via the "Delete" key on my Asus board), go to the "Advanced" tab, enter the "JumperFree Configuration", and you'll see the P5E's overclocking options available to you.