A-frame
I
have both bought and built A-frames.
When
buying A-frames, you get a choice of Framing (Wood, Steel or Aluminum.)
Building
a light wooden A-frame
This
is a modified version of Kurt Glaubs. I highly suggest any home builder
download a copy of his book (definitely worth if for $12!).
I
wanted a light A-frame that would stand up to
the elements better than a hollow core door one.
I
used exterior grade 1/2" plywood and cut the two sheets to 8' x 3'.
Be sure to cut the long boards ends on an angle, which allows the frame to raise.
I
painted the frame and the plywood, with a base coat of exterior.
I
then joined the frame together (with the plywood laying under it).
I
then screwed the frame to the plywood using 2" screws, every 8" or
so. 
To
attach the two sheets together, I used three door hinges per side. The cheap
(>$1.00) hinges you get from Lowes have pins than can be knocked out and
replaced with a 1/4" steel rod.
First I removed the pins. Then I lined them up and attached them to two blocks that were 1" longer than the total length of the three hinges. I also angled the edge at 45 degree so once again the frame could be raised.
Blue
is plywood, yellow is hinges.
1"x6"
blocks
I
ripped 1"x2" in half and then cut them to length, for slats.
I like low profile slats so this worked for me. 
Then
the only thing left was the painting! Several good coats of paint were put on
it.
Oh
yes and chains! Put those on too, using hooks.