[StevieG]

Clayton,

You may know this, but you said noob, so here goes: Generally, you will want to try at least hamachi (yellowtail), toro (the fatty part of the tuna), sake (salmon). Mackerel is also worth a try, but it has a more pronounced taste. Other seafood worth a shot include eel, surf clam, and scallop. Squid and octopus will be tougher (especially if the place caters more to Japanese, since they have a thing for texture) but can be worthwhile. Uni (sea urchin) may be too out there for you, but give it a try, it has a creamy texture.

The best stuff will always be what is fresh and recommended (for instance, the toro peak season is in winter). The chef is your friend here.

If you are adventurous, and can spend some money, the best way to try new stuff in a sushi place is to sit at the bar, and tell the chef that's what you're looking to do. He'll hook you up with fresh and interesting stuff. (That's basically what omikase is, and Nobu is known for, but omikase is going to be a traditional tasting menu and include cooking outside sushi.)

Be prepared to drop some cash, but letting the chef at the bar hook you up really is an experience.

Eating at the bar and asking the chef to take care of me is how I tried such things as Japanese mountain potato (served with a quail egg), jellyfish, and abalone (described by the chef as fish bubble gum -like I said they like that rubbery texture).