edit: I originally replied before i saw that you had started 5 threads on the same subject.
I don't condone that behaviour, so i'm editing my reply.
Yeah, tcp/ip works with civnet. Make sure you choose [...]
One important thing to remember is that when the game asks [...], you need to put in your [...], rather than your [...]. (Use [...] to find out what it is.)
Once you're at the [...]screen, your friend needs to [...]
[...] appears to be the listening port - make sure that is forwarded to your computer by your router. (Use [...] if you don't know how.)
If you use a [...], you also need to [...], civnet and [...]
I'll subscribe to the thread so i can help you if you're still having trouble! 
If that doesn't help, why not try starting another few threads?
