If you don't already have a diamond tipped bit, try asking your dentist for one of their tips (that's where I got my few for my first dremmel tool in high school). Diamond tipped bits aren't very expensive, but their expensive for one-time use. If your dentist won't give you one of their bits, ask if they're willing to drill the hole for you. I don't see why it would be a problem... it's always worth a shot.

AJ