I'll never forget the time my wife and I were dive-bombed by a bat while we were in bed at a lake house. We spent the entire night cowering under the sheets. This was several years ago so this article from Old House Journal on how to rid a home of bats is long overdue for me. Before you panic at the sight of a bat, let it be known that bats are not a threat to your personal safetyóless than one percent have rabiesóbut bats should never be allowed to enter interior living quarters. The article documents the entire procedure of eliminating bats from a home in great detail, particularly useful for owners of older homes.
Many people find that getting rid of bats is not a do-it-yourself project. This is due to the safety considerations with working at extreme heights. Also, you need to ensure that all the little cracks are sealed to prevent bats from entering in a different location. Information on bat removal can be found at: http://www.crittercatchersinc.com/critters/bats/bat_removal_control.html