hi,
i have both a pcmcia and an usb ethernet adapter on my laptop. PCMCIA is detected both in windows and in linux. i use slackware

10.1, but you should be ok because kernel 2.6 detects and loads "most" (all i've worked with) of the usb<->eth adaptors.
if you don-t want to open up the computer, your best / only choice is to buy an usb adapter. i have a conceptornics SP100U. works great with slack. in windows, unfortunately, you need drivers

... "windows... the plug'n play OS

"
if u need anything drop me a line.