numpty online gaming question

[alltorque]

I'm reasonably new to online gaming - need some advice. If I want to play a couple of mates dotted around the country at HalfLife 2 (deathmatch), can I set up our own game for just 3 of us? Or do we have to play on the preorganised servers on the steam site? Is the only way to do it to have our own server?

If we choose an empty site on Steam, people keep joining in (I know, just not on is it!!) and blasting us to pieces.

Any way of creating our own game?