How do I play multiplayer?

I just bought the DOOM Colletor's Edition last night, and a man at EB there told me about DOOMWorld.com and that people still play multiplayer with classic doom. I don't know how to set up multiplayer for this at all. Can someone help me? Thanks.

Taking a minute to read earlier posts would have helped you spot Internet deathmatch doom thread

you could also play multiplayer over a network if you have one or you could play online on numerous places.I think Mplayer has a server for doom i believe msn might too. I got my butt kicked. I think it would be better if i had dsl.