Sushi rolls are pretty easy, as long as you get good sushi rice and are willing to put up with sticky rice all over your fingers.
How to make a simple roll:
http://makemysushi.com/index.php/How...maki-roll.html
To make the penguins, I would make a plain rice roll (no filling), and then add the face. You can use any tasty thing you like to make the face. The cheeks look like they are roe and the beak might be a piece of cooked carrot. The forehead is a piece of nori that is cut to make the stripe. I think the eyes are made from nori, too.
You could also buy a mold and then cut out the nori to make the black parts:
http://www.allthingsforsale.com/egg-...082762043.html
That same side has instructions for making penguins from rice balls, nori and a hot dog (for the beak). No rolling required. That's probably even easier.
http://www.allthingsforsale.com/bent...ce-ball-bento/