I like to leave my raw fish handling to the professionals and for my at home sushi/onigiri making I only use cooked seafood and stay away from the sashimi.
Oh by the way ... remember what happened the last time I made sushi? Knife stuck in the bone of my thumb bringing back any memories? Thankfully this adventure with sharp knives (thanks Kam) and avocado did not produce any blood. So that's a good night for me!
Some things I have learned. Wet hands are a must for handling sushi rice. It doesn't stick nearly as much and other than getting pruny hands - it's great. Instead of hand "ball ing", I put a square of plastic wrap into the bottom of a small bowl (very small - like golf ball size) and then pack some rice into the bowl. Using my fingers (or a spoon if your not into touching your rice) I then sort of pack it down and make a little bowl. Tonight we had lobster - because that's how we roll here in the 207 (Ok - it's $3.49/lb right now and we only needed one chick for this).
So in that little pocket goes a little lobster, some diced cucumber and avocado, making sure not to overfill and to leave a little rice on the sides. Then another little handful of rice goes over the top and gets packed down. Pull up the sides of the plastic wrap and twist it like you would a bread bag to put the little metal tie on (remember those?) you can then pull the ball out of hte bowl and keep twisting the plastic until the ball compresses. I also pack the rice a little more by hand take out of the plastic- then roll in some toasted sesame seeds. Dan makes a little soy dip with the ginger and wasabi. The plastic wrap eliminates most of the mess.
My kids go nutso for these. They also like sashimi (the raw fish variety) though so they are a bit freaky. Oh... and they eat frozen broccoli - like - on purpose!
You can fill the rice balls with whatever you'd like or have on hand. It does take some time to roll them. If the kids are a little older they can make their own and it's fun. We sometimes wrap them in Nori - but it's more expensive and a bit of a pain.