Does anyone know of any good website (besides Ebay, I've already looked) that has for free or for sale detail instructions on the construction of a Teardrop camper/trailer?

Uh, you could put teardrop trailer plans (http://www.google.com/search?q=teardrop+trailer+plans&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a) in Google and see what comes up.

After you do your Google search, here's a starting point that has DIY plans going back to the early days of teardrops (all will require some modification):

http://www.mikenchell.com/VintagePlans/vintageplans.html

also, how to build a frame from scratch:

http://www.teardroptrailers.us/Trailer.html

definately join http://www.mikenchell.com/forums/

i was a member there way before i found my element. the element and teardrops just go together!!!

We originally used plans off the internet, but after we read to use asbestos panels we decided to get newer plans;-).

The Teardrops and Tiny Trailers forum listed above was where we ended up for ideas.

A plan is just to get you started, the real joy of building a teardrop is designing it the way you want it and making it unique.

Check out the forum and all the different designs and have fun!:-D

The hard part is coming up with a basic materials list and dimensions, so you can evaluate whether the capacity and capability come close to meeting your needs.

Wherever a trailer plan calls for a material that is no longer available, or unsafe, it's simple to substitute a more suitable, available material.