u could try going to system tools and network devices firstly to see if any of ur NIC`s show up in the network box there. Do u really need 3? try going with ur onboard device.
Try opening a terminal window and type lsmod to see if your network card module is loaded.
U can also find lots of help about your probs in the tutorials that u can find on this forum and others. U can also goto
www.google.com and find loads of info on there.
Linux isn`t easy at first but keep at it and u will get there :-)