What kind of legal liability am I under if I sell someone an experimental
air craft and then they kill themself flying it? I didn't design the
air craft, but I did assemble it and would be selling it as if I was a
"dealer" representing the company who manufactures it. Is it possible
to write a contract that releases me of all liability? What about the
manufacturer, would they be held liable?

Have an attorney write up your contract.
If any injury or death results from use of the aircraft everyone from
parts makers, to the kit manufacuter to you will get sued.  Your best
defense is lots of liability insurance - in the 10-20 millon dollar or
more range.

a

Peej --

There are differences between countries, depending on regulatory and
legal issues.  They exist even between the U.S. and Canada, two
countries closely aligned in general aviation.  Here's a good Google
search strategy that turns up some knowledgeable comments from Canard
Zone:
liability "selling experimental" aircraft

The suggestion that one consult Ron Alexander's writings for the EAA
is a good one, as the Experimental Aircraft Association in Oshkosh is
an excellent grassroots authority on homebuilts.  (I tried a Google
site search on www.eaa.org for "Ron Alexander" but it's results are
more on the building process.)

Best regards,

Omnivorous-GA
http://www.mooneyevents.com

Yes, you can write a contract that protects you from liability for
this.  However, you absolutely should have an attorney draft it.  You
don't want to mess up on this one.