my suggestion would be to remove the card, get everything you need configured and then add the card back and try to configure it from there.
what linksys card is it? i know the LNE100TX or whatever uses the tulip driver which comes standard with most distro's.
also, if you have another machine, you might want to check and make sure its not a hardware problem, like if you have dual boot or whatever.. does it work in any other OS? another machine if available?