You can either scroll through dmesg or open up a terminal before you plug in the device and type:
tail -f /var/log/messages
Then plug in your reader, with the card inserted. It should pop up the device name that it takes, maybe something like:
If you aren't sure, post the output here so someone can decipher it for you.
Also, a search in the hardware section of the site might yield TONS of results on this
1 more thing...
Welcome to LQ!