Parking is a hot commodity. There is a parking garage on Queen Street, but you will have to pay for it. I'm not sure if they have a weekly rate. I flew to Charleston and then taxied to my hotel, but there was a multi-level parking garage across from the Elliott House where I stayed.
I would check with the Chamber of Commerce and see if they can help you out with hotels that offer parking. Usually it won't be long-stay parking though. I had a Visitors Guide sent to me with alot of information you can get it on the their website.
Charleston is a wonderful town and if you have time, make sure you take the carriage ride around the town. The history and homes are wondeful.
I would recommend a couple of good restaurants, Magnolia's and 82 Queen Street.
Have a great cruise.
2008 Liberty OTS (Caribbean)
2007 Summit (Alaska)
2006 Century, Infinity (Panama Canal), Summit (Hawaii)
2005 Millenium, Voyager of the Seas, Jewel of the Seas B2B
2004 Explorer of the Seas, Constellation (Canada/New England)
2003 Horizon (Bermuda), Summit
2002 Explorer of the Seas, Brilliance of the Seas (Caribbean)