DH and I have no family near by either, so I have to rely on teenagers/freinds also. Fortunately, my neighborhood has several good kids at the right age. My next door neighbor has one more year of high school, but another neighbor is about the come of age (already knows and loves my girls). So I have been lucky.
Also, check in your area to see if they have babysitting services like Fairy Godmothers. Usually they are a little more expensive than the teenagers, but there is a certain peace of mind that goes along with them. The sitters are liscenced and bonded and have to go through certain training. In my area, I pay the service a $7 placement fee, then $8/hour, 4-hour minimum for 2 kids. I normally pay the teenagers $7/hour.
Go out and have a good time!