Check with your Internet Service Provider or look in the alt.irc newsgroup for more information. So this link takes you to Yahoo's EFnet area. TX.US.undernet.org Chicago-R.IL.US.Undernet.org Dallas. WI.US.undernet.org Springfield.mo.us.undernet.org StGeorge. For DALnet this is 7000.
Many servers have a wider range of ports available.
Also check the network's Web sites. Connect Execute your IRC program. Now you are ready to connect. This is done in different ways on different programs. Be aware that you cannot talk to someone on another IRC network.