"pinning" a package

["John Klassa" <klassa@nc.rr.com>]

I tried to follow the directions, with respect to "pinning" a particular
package.  Specifically, I went to the main debian site and poked around
in the package list, and found that "gnump3d" is available in the
"testing" tree (or whatever the correct terminology is[1]).

	http://packages.debian.org/testing/sound/gnump3d.html

Anyway, I tried "apt-get install gnump3d/testing", but got no matches.

What am I doing wrong?

Thanks,
John

[1] I'm a first-time debian user.  So far, I love it.  I've been using
Red Hat for years and years, and finally decided to try a different
distro.  This "apt-get" stuff *rocks*.