2) Choosing your metals...

The bits you need and where to get them...
You need:
1) Bottom Bracket Shell - I went with lugless 68mm english thread - steel
2) Headtube - 36mm x 200mm for 1 1/8" threadless headset - steel
Alternatively you can look at the miter posting on this blog and find a description of how to make a hemp fiber headtube.
3) Some kind of seat tube or seat tube shim. I went with a seat tube 28 x 9/6 x 650 mm
This however is a problem left unsolved. I haven't yet gotten to the point where I need to attach a seat. So either I will keep a long bamboo tube and fit a seat directly to that, or I will ream out my bamboo seat tube and sink the metal on into it (this is probably preferable since the seat tube takes a huge portion of you weight and the strain from peddling). I would not recommend sinking the actual seat post directly into the bamboo and then clamping it. This would likely crack you bamboo...
4) Dropouts - I would recommend something like this. Although Im not of fan of track style dropouts but what you are looking for is longer arms so that you have more room for error. Also keep in mind that each bottom bracket has its own fixed angle...
5) Any add-ons you might want, water bottle bosses, cable guides

Where to get it:
There are a number of bike building suppliers (here's a good list).

Material types
Aluminum - its light its cheap and you can get it off your old jalopy bike. Which is handy. The only problem is that aluminum apparently requires special chemical preparation for bonding with epoxy, or at least I read that somewhere. You should be able to find out more from the West Systems site. "Sand and prepare with 860 Aluminum Etch Kit."

Steel - sure its harder to come by but you can always buy it. Steel is more pliable, which could come in handy, and does require anything more than a good sanding to join with epoxy. I have been having a bit of trouble with the epoxy bonding to the surface of steel so I looked at the west systems site. Here is what they say to do: "Remove contamination, sand or grind to bright metal, coat with epoxy then sand fresh epoxy into surface. Re-coat or bond after first coat gels." So I guess I wasn't doing it right.

Some Notes On bonding:
Surface prep can't be overlooked. It is critical that all the surfaces bond properly together.
Since bamboo is an waxy wood you need to make sure that you both attempt to sand down the poles where you will be bonding them until the dull brown fibers are exposed. Believe me the epoxy does not bond well with a waxy surface. You then need to strip the surface further with a strong solvent. West systems suggests using acetone, this stuff is toxic as hell so use it outside and with your respirator if you have to. Apply and attempt to remove any extra wax 15 mins before applying epoxy. One alternative is biosolve by mas epoxy. This stuff is much better over environmentally.

Bonding:


Applying fabric: