From Bible History Daily:
In the Book of Joshua, Rahab (a heroine nonetheless known as “Rahab the Harlot”) assisted two Israelite spies in escaping out a window and down the city wall of Jericho. Who was Rahab in the Bible? A Biblical prostitute or just an innkeeper? Did she live on the wall of Jericho or within it, in what is known to archaeologists as a casemate wall? Anthony J. Frendo addresses these questions about the life of Rahab in the Bible in the September/October issue of Biblical Archaeology Review. Whether or not she was a Biblical prostitute, archaeology may at least be able to answer whether Rahab lived on or in the casemate wall of Jericho.
More on Rahab:
Rahab the Prostitute from about.com
Rahab - The Woman God Took From the Dunghill from Bible GatewayProfiles of Faith: Rahab - From Harlot to Heroine from the Good News
Who Was Rahab The Harlot? from Share Faith