The best solution is to get a travel router that allows you to spoof MAC addresses. I think you initially make your connection with the laptop then have the router duplicate it's MAC address. I've not tried this though, but people claim it works. The other thing I've heard works is internet connection sharing from the laptop. I never done either that you'd have to do some research. You should be able to find information about either idea on the internet.
I tried ICS on a different computer, a netbook with XP, and had no luck getting the computer to share. I am sure it was my problem, not the computers.
Regarding spoofing a mac address, could someone help with how to do this. I have searched here and googled the term and don't quite understand how to do it. Do I need a router to do this, or can I do it with the computer only, then connect the Roku to the provider.