I just came across the National Campus and Community Radio association (Canada) program exchange and thought I would share it here.You need to be a member to use the content from the website, but if you see something you like - I bet you could contact the creator directly and ask permission to rebroadcast it.
Visit the NCRA Program Exchange at http://exchange.ncra.ca/ ."
From the website: "The NCRA Program Exchange simple way for radio producers to share their programs with other stations and a great place for radio stations and programmers to find programming to air, whether complete programs or segments that can be incorporated into other programs.
The Exchange is searchable by topic, program type, program length, producers, series etc. NCRA members can log in and download content for broadcast on their stations. Anyone, member or not, can browse the Program Exchange and listen on line to the programs archived there."