Kaiseki can be found in a few cities in the US, including at Silk, in Atlanta. It’s worth the time and price involved. The experience is unique, and be sure to go with a mid-to-high-grade cold sake, like kikusui. The non-filtered and country sakes are a revelation in taste.
Sushi and Sashimi are a bit challenging to the American palate.
Think initially in terms of a few characterisitics:
Cook-i-ness: Raw, Cooked, Cured …
Texture: Squishy, Soft, Firm, Chewy, Smoked …
Heat: Spicy, not-Spicy, kinda-Spicy …
Flavor: Sweet, Savory, Sour, Fishy …
Start with the safest options, initially:
Tamago Nigiri(cooked sweet egg custard on a bit of sushi rice)
Kani (or Kani Kami) Nigiri(cooked crab or imitation crab meat on a bit of sushi rice)
Start with cooked, and then go to … smoked …salmon, that is.
Then go to the raw stuff, but stick to firm raw, and not too fishy.
Then branch out into the more challenging stuff, like squishy/chewy: Roe, Tako(Octopus), Squid, …
And Tuna … try all three cuts: top(Hiro-maguro), middle(Maguro) and bottom(Toro).
The best minimal presentations are Sashimi(just thinly sliced raw fish) and Chirashi(think tossed sushi-rice and sashimi salad).
And get the Osaka-style hako-zushi, which is basically pressed layers of rice and toppings.
My preferred chef will make stuff up for me - things like spicy tuna hakozushi, lobster-mango tempura roll, kani-kiwi-miso salad, lobster ginger hakozushi. The stuff is addictive.