looking for address and phone number of company that manufactures and
sells Curtis Stereo system Model RCD637.  It is not the Curtis
Technology in Rockford <IL.

I think you're looking for the following:

Curtis Stereo is:

Curtis International Ltd
315 Attwell Dr.
Etobicoke Ontario Canada M9W 5C1

Phone: 416-674-2123
Fax: 416-674-2135

(If you're not dialing from Canada, you may need to dial the country code first.)

Confirm this at: http://www.hoovers.com/co/capsule/6/0,2163,57306,00.html