The wall outlet is probably already supplying a internet connection. If so, you need to set up the Linksys wrt54g v8 as an Access Point, not a Router. I don't know about the Linksys but normally setting up a router as an access point involves turning off DHCP and changing the IP address of the router to one within the range of the wired network.
However normally networks are configured to be secure and one way of doing this is to limit devices connected to the network to a pre-set list of MAC addresses. The MAC address is unique to each item of hardware, it's a string of characters separated by colons. If you are not seeing an internet connection it may well because of the security filtering, the MAC address of your Linksys is not on the list.
Thanks I'll try changing the dhcp.I don't think its a whitelist issue as I have reset the lynksis so its not blocking anything.
The network here is dsl, so The telephone wire goes through an adapter and to the Ethernet cable. There's no other device involved.