What you need to do is either google for the name of the servers in your area, or else just call comcast.
I was trying to get this to work myself yesterday.
Once you have the proper info, just enter that into the setup menu, then enter your username and password under incoming, and leave outgoing blank if you don't have some kind of added security.
The trick is you will have to wait forever (probably) while Touch contacts and confirms your server. If you don't have security, click "connect without SSL" (say yes...) when Touch asks.
I have had shaw cable for a long time, and when I first got my MacBook I got frustrated with Mail because it was taking so long "trying to connect" that I assumed it was either crashed or refusing to work. Be patient with it.
Trust me - the iPhone mail app is worth it!
One more thing: if you're using Thunderbird or any other mail program to get your email, you may want to change the settings about deleting stuff off the server. Otherwise, if you go on your computer and download new mail, you won't be able to get that stuff on your touch anymore (since it will be deleted from the server).
Hope that helps.
As for summerboard, the one under installer app apparently doesn't work - I can't get it to cooperate. It just messes up my dock. I'm prepared to live with my appearance the way it is