Catalina has excellent products. I order from them a couple times a year for difficult to source items like tobiko, masago, and unagi. I did get an order of Hamachi from them that was less than spectacular though. Shipping is kinda expensive too, but they have to send overnight with icepacks. The unagi they sell is from the same company that most sushi bars buy.
I usually buy my fish locally. Sometimes the Yellowfin at my local grocer is good enough (use your senses, especially your nose). Whole Foods' processed fish (steaks/filets) are expensive, but usually of good quality for eating raw.
Nick ~ "Egg whites are good for a lot of things; lemon meringue pie, angel food cake, and clogging up radiators." - MacGyver