IPAQ to Airport connection


Just put my toe into the dark side andgot myself an HP iPAQ 6340 with the itention of connecting it to the internet etc via my airport. Whilst I 'seem' to have a connection with the base unit and the iPAQ is telling me that Wi-Fi is active, when I go into Internet Explorer, I can't access the web. Trouble-shooting suggests I've not got my security settings right and then when it starts getting confusing...
Any suggestion. Cheers