How do you set up an internet connection so that when users connect via wireless they are redirected to a welcome page ie in a hotel or public access point?

I have used this product in several commercial applications.. it works great and it's free

http://www.publicip.net/ What happens here is the users will see a the SSID of your AP. Once they double click to attach to the AP they will be redirected via the gateways "publicip.net application"

• once signed in they can surf the web.

From your perspective you need a AP - Router - Server to run the aforementioned software.