You need to book in advance, you can usually find a flyer for the service at any of the hotels or if there is a ticket desk just ask them. There are pick ups at Universal, Mercado and Sea World, I think there is also one on highway 192. It takes 1.5 hours to get there with the arrival timed for about 10am. The pick up at night will vary depending on the closing time of the park. Last week when I was there the park closed at 6pm and the pick up is then. The cost is now $10 per person unless you have the 5 park flex ticket which includes the shuttle. Personally I think the service is excellent, although I had a car the thought of driving back to Orlando after 8 hours in Busch didnt sound a good idea to me.