They are the same as auto bulbs. I believe they are an H4 and an H7 (I'm not sure which is high beam).
There are alot of "after-market bulbs with higher wattages and "brighter" lights, some even change the color from bluish and purple to yellows.
Be careful with higher wattages. Your wires are designed for the standard 50-60 watts (give or take). If you exceed that by too much you can actually burn up your bulb sockets and wires.
I've been lookin' around for awhile for brighter bulbs and I think Sylvania makes one called the Silverstar that is supposed to be really bright and is the stock wattage.
I have also been toying with the idea of HID.
Hope this helps.