I also realize that I am something of a philistine, etiquette-wise, when it comes to sushi. I'm learning, though.
A nice basic rundown on sushi etiquette.
More of the same, with a few new details.
(Of course, one can note that the etiquette for sushi eating is a little more relaxed in little old Madison than it would be in New York or Tokyo. We're all philistines round here. :)