I found this in the new items part of hobbycity. They have carbon fiber in 200 and 100mm sheets. It comes in 1mm, 1.5mm, 2mm, and 2.5mm thicknessess. Prices are $20 for the thickest and under $10 for the thinnest. It's not big enough for a whole chassis, but it would be great for making custom carbon fiber parts.
2.5mm -
http://www.hobbycity.com/hobbycity/s...idProduct=8709
2.0mm -
http://www.hobbycity.com/hobbycity/s...idProduct=8708
1.5mm -
http://www.hobbycity.com/hobbycity/s...idProduct=8707
1.0mm -
http://www.hobbycity.com/hobbycity/s...idProduct=8706