Nell Morris Cribb, a Georgetown native who conducts tours wearing period dress, complete with a bonnet, provides personalized walking tours of the downtown Historic District. Miss Nell's Tours takes in about 12 history-rich blocks, lasts about 1 1/4 hours, and costs $5 to $9 for adults (free for children 12 and under). Tours begin at HarborWalk Books, 723 Front St. (tel. 843/546-3975). The tour is given Tuesday, Wednesday, and Thursday at 10:30am and 2:30pm and on Saturday and Sunday by appointment.