I like sparkfun electronics...
http://www.sparkfun.com/commerce/categories.php?c=23
They have a lot of other cool stuff too...
Hmmm Hot... well SOME electronics run hot.... but I don't think Accelerometers or gyros should ever run hot. If you're coming directly out of the analog breakout from the NI9201 and using a pwm connector, you can only get 5V so that shouldn't heat up.
If the accelerometer has a short in it, that COULD cause your analog breakout to get hot. I usually like to see sparks shooting .. that always helps pinpoint the problem.
Good luck
Steve