package sources and zlib

[Mauricio <supremedalek@hotpop.com>]

	Quick question: can I have more than one source for packages 
in /etc/apt/sources.list?

Also, why wouldn't I be able to get zlib:

katrina:/home/raub/todo# apt-get install zlib
Reading Package Lists... Done
Building Dependency Tree... Done
Package zlib has no available version, but exists in the database.
This typically means that the package was mentioned in a dependency and
never uploaded, has been obsoleted or is not available with the contents
of sources.list
E: Package zlib has no installation candidate
katrina:/home/raub/todo#

Incidentally, this is how my /etc/apt/sources.list looks like:

katrina:/home/raub/todo# cat /etc/apt/sources.list

deb http://ftp.debian.org/debian/ stable main
deb-src http://ftp.debian.org/debian/ stable main
deb http://non-us.debian.org/debian-non-US stable/non-US main
deb-src http://non-us.debian.org/debian-non-US stable/non-US main

deb http://security.debian.org/ stable/updates main
katrina:/home/raub/todo#