You have to try before asking for help.
Find out the make and model of the card ie. D-Link DWL-G510 rev. C
Look for the Linux driver that will make it work. <-- there may be more than one. Read about peoples experiences with the card and drivers. The driver I use for my card is madwifi.
Learn how to install the driver. Either by source or as a package, whatever is needed.
Learn about: ifconfig, iwconfig, route, nslookup, ping, lspci, and resolv.conf <-- these are for configuring and troubleshooting your network.
I remember finding a really good wiki about linux wireless so check there and remember that google is your best friend.
If you want to leave the noob level then you have to try things out for yourself and learn from the experience. If you have problems that you can't solve after doing your research and trouble shooting then revise what your asking for. Give us the make and model of the card, the driver your using, the distro your running, and give a detailed explanation of whats going on.