I hate those mices [pronounced meeses] to pieces!

I've been very fortunate so far (for a newbie) getting SuSE 8.2 to work
on my PCG-R505DSP, thanks in large part to this list.  However, I'm
stuck on one problem that stumps me.

I use the touchpad (ps2aux) mouse when I'm not in my office and am
undocked, and I use a Logitech Cordless Tackman Wheel (imps2) when I
am.  Of course this was a non-issue in WinXP.  How do I make this a
non-issue in Linux?  Meaning, I want the machine to switch between them
automatically.

If I can't have 'automatically', how close can I get?

Thanks everyone.

Luke