When Fair Use doesn't apply
If you have determined that a work is still under copyright and your proposed use is not fair use, then you need to obtain written permission to use the work.
Finding the Copyright Holder
The University of Texas Getting Permission web site includes information about finding copyright holders and contacting collective rights organizations for permission. Collective rights organizations are groups that serve as agents for copyright owners to receive and process requests for permission to use copyrighted materials
The Copyright Clearance Center provides a service for requesting permission to use copyrighted materials, and covers nearly two million copyrighted works, primarily text-based works (books and journals). In many cases permission can be applied for and granted instantly online with the payment of the required permission fee.
Writing for Permission
You can use the Sample Permission Request Letter as a basis for requesting permission from the copyright holder. There is no required form for requesting permission. If you chose not to use the sample permission request, your permission request should at least include the title of the work, the name of author, artist, or editor, a precise description of what you want to use, and a description of how you intend to use it (e.g., copy, perform, display, make a derivate work, etc.). The more precise you can be in your permission request, the more likely it is that your request will be approved. Make sure to allow sufficient time for your permission request to be processed. In many cases 4-6 weeks may be required.