Originally Posted by wondering why

Their spam files and if you download them you will end up infected...

So if these are the only results you are getting try going 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...
(try to take note of the hosts IP numbers if the same ones keep re-appearing add them to your host filter...)

Tools > Options > Filters and select the Host Filter and add these IP's into it and select apply...

Try installing PeerGuardian, it will help keep the fake hosts out...Remember to enable PG just before you start limewire up...
Phoenix Labs » PeerGuardian 2

If you're using Vista, there's this PG2 Beta available for Vista users.
PeerGuadian 2 for Windows Vista beta released - Phoenix Labs

PeerGuardian 2:Manual - Phoenix Labs Wiki


Another thing if you are using limewire 4.13 and later you can apply this hostile list...This will block known fake IP addresses...

The TechNutopia Fullsize Hostiles List for BearShare and LimeWire