Re: App question
I believe it's because the app creates an ad-hoc network as opposed to a standard WiFi network.
You could try searching for for the Rezounds wifi-tether app, but there may be hardware issues, software incompatibility, and other issues.
Do you happen to have a home computer with internet access? If so, how is it connected?
At home I use my PC as a "wireless router" for my xbox. If it's possible for you to do the same, I'd be more than happy to show you how to do so (provided it's a Windows based PC :P)