Really, all there is to the general USB configuration is to ensure that you have a kernel that supports it. Since I usually compile the latest stable kernel and track that, It's not a problem. However, there are some gotchas wrt USB. If you have a Handspring Visor as I do, and you want to use it with your laptop, then you need to makesure that the visor module is compiled. It's under the USB serial converters section in the kernel config. Also, you will need to mknod the /dev/ttyUSB* files, I did this (as root) by cd'ing to the /dev/ directory, and running the following commands.

This created the device files I needed for the visor, you can go ahead and make /dev/ttyUSB2 and ttyUSB3 also if you want.

Now when you press the hotsync button, the machine will beep twice (or it should, if you added the visor module to the /etc/modules file. If not, you need to modprobe visor and that will load the visor and any other required modules.)

For usb mice, the XF86Config-4 I mentioned earlier has the requisite lines for a 3 button mouse with scrollwheel.