Could be a LOT of things causing this...
Originally Posted by Danielle Byrd
First is your router... I've seen problem with compatibility between brands and devices, so it might be a question of testing out with another router.
Also... settings on the router... check if the router is seeing the Touchpad. if yes, it still could be a problem with the IP being provided but with a conflict... possibly with another device, restart the router's IP (release and refresh) if you can (varies from router to router), then reboot the router and all devices.
So, I'd start with insuring that the Touchpad is connected to the router, then if yes, renew the IP.
If still no internet, test your Touchpad at a friend or free WIFI somewhere, if you have a Pre (or another phone that can teether with the Touchpad), teether it to your phone.
What it comes down to, you need to see if it's the Touchpad or not, and even if you have other WIFI devices that work, it could still be the router.