Modifying Graphical Login

I would like to modify the graphical login a little. I installed the gdm 
package and recompiled it. But I had two problems

1) I don't know how to apply the patches that come with it. Just doing

patch <patchfile name>

doesn't do anything. Maybe this doesn't matter because of the following...

2) Compiling the sources (without the patches) gives me a different gdm-binary 
that is MUCH bigger than the one that RH 9 installed. Where is the source, if 
available, for the version of gdm that is standard with RH 9? Or am I missing 
something? Should I be modifying a different binary?

This is my first post, and I hope that it is appropriate for this list. If 
not, I am sorry.

Thanks for any and all help

James