Take your best route to the south US 23, or simply get on south I-75.
Head south on US 23, or I-75 and continue until you reach I 80/90 tollway in Ohio. Head East on the I 80/90 tollway (the average toll was $6.00 last year). Stay on I 80 all the way to Pennsylvania. Do not get off I 80 inside Ohio! Also, do not accidentally take I 76 south when I 80 splits near the Pennsylvania border (this has happened before, and will add 1.5 hours to your trip). Continue to the I 79 interchange and head south. When you get near New Castle/ Slippery Rock pay attention to the right side of the road (you can actually see the huge campsite as you get close. At night it is a huge glow, and can be seen from the road even better).
Get off at Exit 29 (Signs for Route 422 West). At the end of the ramp, turn left (towards Newcastle PA). Go approximately 3/4 miles to the sign for Cooper's Lake Campground (the sign is small and will be on the right hand side of the road). Turn right (this is Currie Road). Follow Currie Road, until you see the signs for the Troll Booth. Please follow the directions of the Parking Directors.