I have a similar problem, but it's not on my network. My 3rd gen 32GB Touch can connect with no problems to every network I come across. And I can access the internet from all except one. My kid has karate lessons and the school has free wifi, my Touch connects to it fine but no internet. Odd thing is my work and personal laptops connect and reach the net with no issues.
I have checked and rechecked settings on the Touch and all looks good. I can't figure out the issue. Anyone have any ideas? anyone else experience issues like this?