To play on the server:
open console and type: connect zoma.dtdns.net

Maps:
1) l4d_vs_billys_farm
Download current version:
http://www.sendspace.com/file/243905
or
http://www.sharemania.ru/0296500

2) l4d_cottageofdoom_b1
http://www.fpsbanana.com/maps/80378

3) l4d_vs_billys_farm_se
"Special Edition" :D
http://www.sendspace.com/file/bxxs4c
http://www.sharemania.ru/0245682

HOW TO CONNECT TO THE SERVER:
open console and type: connect zoma.dtdns.net
or: the server name is ZombieMarathon
Start the game, open console and type: openserverbrowser
Then look for ZombieMarathon server.

NB! Not always online!

sv_search_key ZM