If you can do it (I know some people can't) you could go with sashimi instead of sushi. Just fish, no rice. I was strictly a California roll gal for a long, long time, I once tried a piece of yellowtail sashimi that my husband had and didn't like it. However, a few months ago I tried a bit of something called spicy tuna kabachi, which is small chunks of fresh raw tuna in spicy sauce... and I loved it.

I started out just eating a few bites and now I have to get my own appetizer of it or my husband doesn't get any at all. Since then I have been brave enough to try larger pieces of sashimi, even yellowtail, and have really enjoyed it. The trick is to let them know you are trying new things and experimenting... the staff will love to help you out, more than likely. Ask for mild flavored fish, too, that seems to help. Start with small small small pieces....
If you can't bring youself to do it, though... I dunno... Anyone else?
Good luck!
-Lala