differently than the other cod games, cod5 uses demonware for all the online stuff and this covers also the servers list.
while on Enemy Territory Quake Wars (which uses dw too) exists a web based servers list available just by the same dw (
http://etqw-ipgetter.demonware.net/ipgetter/), codwaw doesn't have the same ipgetter service so the only "native" alternative is getting the list through the dw protocol (although I don't have the game I made a small research some time ago but without nothing ready to use).
so I guess that doesn't exist a real alternative because even Gamespy doesn't support this game (codwaw and callofduty5 return 0 servers in gslist)