It's weird -- there used to be a lot of yellow helmets available. The Giro that I crashed in (my dog accident) was yellow, and my husband still has a bright yellow Giro he bought a few years ago. I guess there are fashion colors in helmets just like with everything else. It does seem irresponsible of the manufacturers not to supply a nice visible color choice like yellow.

They do make little yellow reflective stickers you can put on the back of your any-colored helmets, though. Performance sells them, and I am sure other LBS's must as well.

Good luck!

Emily