An animated MP3 player that takes the form of the robot--whose name stands for "Waste Allocation Load Lifter, Earth Class"--is available for order from the Sharper Image. (Maybe it hasn't gotten much notice because of the chain's uncertain future.)
It's not the $190 "Ultimate Wall-E" full robot, but the 8-inch-tall "iDance Wall-E" does claim to talk and dance to the music while its eyes light up. Plugging into an iPod or other MP3 player, it sounds like another version of the "i-Dog," "i-Cy," and i-Everything Else. And at $25, maybe you can save some money and fool your kid into thinking it's the big Wall-E--for a couple of minutes, anyway.