I'm planning to donate a piece for this great cause as well! I'm not sure which one yet but you'll see it posted on the Artists for Japan Facebook page when I figure it out.
Here is the information from the page if you wish to see items donated or purchase an item:
About: Handcrafted beaded art and jewelry to benefit the American Red Cross' Japan relief effort.
Description: This page contains handcrafted beaded art and jewelry. All work has been donated by the artist, with the proceeds going to support the American Red Cross as it helps the people of Japan begin to rebuild.
Purchase of these items will not only make you feel good as you wear the item or display the piece, but will also make the difference in a person's life.
I just want to note that there are many artists, not just bead and jewelry artists who have posted about items they are selling and donating the proceeds from those sales to the American Red Cross or other relief groups. Please take a look at those items as well!