How to find missing libraries when compiling apps

[CB]

On Tue, 2004-09-28 at 02:10 -0500, Michael wrote:
> One of the best recorces to find dependencies is rpmfind.net if you
> cant find them through your update manager.  The package it said was
> needed is "gdk-pixbuf"  You can get it from this mirror in a source
> rpm and just use rpmbuild --rebuild file.rpm.src to build it for your
> system.
> 
> http://mirrors.kernel.org/redhat/redhat/linux/enterprise/3/en/os/i386/SRPMS/


I realise this may sound none-too-bright, but I'll risk that and ask
anyway: how do you get from the message 'No package 'gdk-2.0' found' to
knowing that "gdk-pixbuf" is what's needed? Is it just that you already
knew this or is there a method of finding what packages a given library
is in?

Also, does anyone know where I might read about the whole context around
libraries on linux (stuff like: standard locations, how to find out if a
given library/version is installed, commandline tools related to
libraries etc).