prioritizing deb locations

["Monique Y. Herman" <spam@bounceswoosh.org>]

I've only recently developed an interest in pulling a certain package
from a repository I found on apt-get.org.  I added the line to
sources.list, et voila, I get the package.  Easy enough.

Is there any way to tell my system that I only want certain packages to
come from this source?  I guess my fear is that someone will put a
bleeding-edge version of a package into the repository I'm using for
other reasons, and now suddenly I'm pulling this non-official package
into my system, rather than the one from the official debian repository.

-- 
monique