WI - FL spring break 03

Four of my friends and I are planning a road trip From Madison, WI to Destin, FL for spring break. We plan on taking a suburban. We are going to Destin first to stay at my grandparents' condo on the beach. Later in the week we want to get a campsite at st. andrews state park in Panama City to be close to all the spring break action.

Any must sees or party spots along the way? (WI - FL)
What would the approximent cost for gas $ ??
campsite prices?

Any tips or suggestions would be greatly appreciated

Respect