Cloned Mac address conflict OSX.3 Please help.

Hello, I am in need on help. I searched the forums first, but to no avail. I have an Ibook I bought new last month. My home network is wireless, but to transfer large files, I just plug a network cable (not twisted pair, standard cat5) in the two pc's, and it takes minutes, not hours to transfer 4.35 gb files.

Well, I had to clone my mac address in Ibook's ethernet port, to my windows pc ethernet to trick a program into thinking it was talking to my mac, not my pc. It worked great, but I forgot to unplug the two before I cloned the mac address, and the two will not connect anymore, only wirelessly. The instructions warned the network would be seriously screwed up if I had them on the same segment, but it didnt say how to correct or where to look for help.

(and yes, the warning was in a FAQ at the end of the instructions, I usually catch these things.

Any help would be greatly appreciated.