Congrats!! Sounds like you're getting into it already. I hope I (we) didn't come off as a "bike snob", because I believe that it doesn't really matter what you're on as long as you're out there riding.
As for seats; it's really up to you and your tush as to what's right for you. I think you've posted about Selle Italia seats before, and they are great seats, but everyone's back side is shaped differently so what might be comfortable to you would just kill me.
Some people go crazy for Brooks Saddles ( http://bicycleseatreviews.com/category/brooks-saddles/ )but it's really just a piece of leather stretched over a metal frame...not terribly comfortable to me.
Others go for the modern version: http://www.bikesomewhere.com/bikesom...0597?i=default
Which is just a piece of carbon fiber shaped like a bike saddle.
If this will mostly be a commuter bike/ grocery getter you may want to look at a lower profile gel seat. Not the sleakest thing around, but very comfortable.
To start off I would probably look at something in the mid-size and mid-padded range. Not too hard, not too soft, but juuuuuust right.
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong, it usually turns out to be impossible to get at or repair."
-Douglas Adams, Mostly Harmless