* Configuring a Router for use with a Dedicated Server @ Steam <-My personal favorite. It covers almost everything.
* Required Ports for Steam
* Port Forwarding Guides for Steam Client @ portforward.com
* Opening Ports for Steam Server on the Microsoft Windows
Note that you need to forward both TCP and UDP in your Windows Firewall and Router.
Oh, and a easy beginner mistake to do: If you login after seeing your server in the LAN section of Steam. Don't forget to check so that you are not hiding password protected servers. I remember I thought my ports wasn't working. But it was just that I had hidden unofficial password protected servers.
