Backstage.  Check out the "Performer's Resource" ads for acting schools and coaches, singing and vocal coaches, and so on.   "Career Chat" may also be helpful though much of it is accessible by subscription only.

National Association of Schools of Theatre.  Listings for 115 institutions accredited by the organization; answers to frequently asked questions.

University/Resident Theatre Association. A selective group of professionally accredited graduate theater programs "where advanced students and professional theater artists work together to encourage achievement in production and performance" as well as university-based production companies.

WWW Virtual Library: Theatre and Drama.

Yahoo: Theater Education.