I am a Linux newbie. I have installed and used a few different distributions in my job. we manufacture embedded systems hardware and our customers install various OS's. I am going to be installing Redhat 9 to try to duplicate a customer's problem with USB tomorrow morning. I am thinking he might just not have the latest drivers. Where is the best place to find/download something like this?

http://freshrpms.net/
http://search.rpmseek.com/search.html

If using old 2.4 kernel based distros then USB can be a bit problematic. Upgrading to the latest 2.4 kernel may help sort out your customers problem.

He's right, but then the nightmares start. Updated kernel modules, finding the kernel, finding the kernel source. If you don't understand any of this you are in for a learning curve. Any wise computer professional will suggest the least path of resistance and the lesser of the evils. Updating your kernel is not for a newbie.

Reproduction of your customer's install is going to be extremely hard since any package can be installed which may modify any number of potential parameters and cause imprecise results.

Linux isn't easy for the beginner and debugging complex issues where you have to reproduce an environment will be a complex task.