If your ancestor was an innkeeper in colonial America, you might be fortunate enough to locate records of his proprietorship, such as log-books and tavern petitions, at a historical society. However, if your ancestor was the proprietor of a tavern (also referred to as a "grog shop" or "dram shop"), he or she was required to file a petition, usually through Inferior Court, for a license which was annually renewable. When opening or relocating, an inn or tavern owner advertised in newspapers by giving a statement of proprietorship and the location.
Probably the most comprehensive source for the subject, though, is Alice Morse Earle's Stage Coach and Tavern Days. Originally published in 1900, this illustrated study covers the major taverns of the 17th and 18th centuries. This 449-page book was reprinted by Corner House Publishers, 1321 Green River Road, Williamstown, MA 01267.
The Flagon and Trencher: Descendants of Colonial Tavern Keepers was established in 1962. Its goals are to collect information on taverns, tavern keepers, tavern customs, recipes, and menus. It also maintains genealogical records showing descent from colonial tavern-keeping ancestors. Membership is limited to those who can prove direct descent from an individual operating a tavern, inn, ordinary, or other tye of hostelry before 4 July 1776. The Society does not offer a search sevice of his files. For a membership application, send a self-addressed, stamped envelope to Mrs. Barbara Carver Smith, C.G., Keeper of the Tavern Records, 850-A Thornhill Court, Lakewood, NJ 08701-6661.
Reba Masterson Shepard's Index to Volumes I Through X, The Flagon and Trencher, Descendants of Colonial Tavern Keepers (Stuart, FL: the author, 1995), is accessible at the Family History Library in Salt Lake City or via microfilm loan through its regional Family History Centers. The film number is 2055233, item 6.