If you stay on Carters Ferry Rd(the road you turn off of to get to San Miguel) and go to the next intersection(1215) turn Right and in about half a mile is a ramp on your right. You kinda go behind this guys house and the ramp is there. He's friendly and usually comes out to make sure people get launched ok. I think its $5 and there is a place to put it if you don't see him. Per google its 3 miles from the San Miguel turn.
"I'd Rather Be Fishing"