Ok a few things, firstly we will start with your router...
You have said that you have port forwarded, just check to see if it is configured correctly
These are your instructions..Check which one is yours...
Port Forwarding for the Linksys WRT54G v2.02.7 Port Forwarding for the Linksys WRT54Gv2.04
Also try this...
Go to your connections Tab in limewire, if it's not showing up go to Veiw > Show/Hide and make sure the connection tab has a tick next to it...
Then click on the Hosts and remove them and let Limewire search for some more...
It is also wise to go to your Filters, to find this go to Tools > Options > Filters and select the Host Filter and add these IP's into it and select apply...
And see if that helps...