I have a linksys router and Im using the "spoof" method. However I seem to be getting the same few ip address's. I go into the router basic set up, go to "mac clone" and change the last letter in the last box. [8A] letters A to F. But this week starting on the 19th I keep getting the same 5 ip address's. Is there a limit of how many times I can do this? Or is there something else I can do to the mac address? I dont want to mess up the router. I was also reading in another thread here in WIMIP that something can be changed in the modem, is that correct? How would I get into the modems "control Panel"?
Try changing the second to last number in the mac and see what happens.
If you still get one of the same IPs, your ISP may just have a block of IPs allocated for your 'range' which is probably something triggered by the modem.
As far as getting in to the modem, I'm sure there's an interface. You may want to hit the manufacturers page of the modem and see if they offer a setup guide.