I use the same shield as for the Arudino , it fits. It does not cover the extra headers so those are available.
This is a kit that needs soldered. It's effing half the cost of an arduino!
http://www.sparkfun.com/products/9346I see several online, I have no clue about them. The sparkfun looks the best.
I've taken to just using my giant and mini bread boards. If I want a permanent solution I'll either buy another unit or find one of the bare bones ones. I was considering a freeduino epic that has no headers or usb but I can buy a whole mega for the same cost.