I wanted to assemble a Zendo set, so I needed to locate single-color Icehouse stashes, stones, and rule cards.

Pyramids.

fairplaygames.com has orange, purple, and white, each for $6.95
These are the original stashes as sold by Looney.
I bought these.

4triangles.com has any Rainbow (or Xeno?) color, each for $6.99
These are assembled from Treehouse sets and you can order them through Amazon. They don't include the D6. I got yellow, red, and blue so I'd have a contiguous spectrum. :-)

warehouse23.com has blue, clear, and yellow, each for $8.00
I didn't order these so I don't know how they come, although I suspect they're original stashes.

If you're getting more than one stash, it looks like any of these deals beat eBay, because of the shipping charges.


Stones.

At first I looked at glass stones, and realized that real stones would be much nicer. So after hunting around, I discovered gemsofgaia.com, and ordered some from there via ebay. There are about 30 stones in a 1/2 lb order of medium size, and they are very pretty, tumbled quite smooth, and surprisingly uniform in size. Nice for fondling, if you're into that sort of thing.

Here's what I ended up getting; each cost $7.99

magnesite (for the white stones)
snowflake obsidian (for the black stones)
red jasper (for the guessing stones)

Cards.

I made a set of 52 cards with beginner rules on them, printed on cardstock, and cut. If anyone wants the PDF, message me and I'll email it to you. They're currently written assuming the colors are orange, white, and purple. Eventually I'll change this to red, yellow, blue.

Edit: See here for the R/Y/B cards: http://www.boardgamegeek.com/file/info/27302

Tested the shebang last night on some friends (mixture of gamers and non-gamers), and it worked well. We played with very restricted rules (exactly 3 pieces, only 3 colors, only beginner koans).

The only frustration was that we ran out of colors pretty early and had to double up (yellow=white, blue=purple, orange=red). This is especially hard for a beginner, so If I were to play this really often I might get one or two more stashes of the main three colors (probably blue, yellow, red).

I'd also made Martian Coasters in the appropriate colors and a Volcano board for the same colors. (message me for a PDF) We tried one game each of Treehouse and Martian Coasters, but spent most of our time on Zendo and Fluxx (which someone brought to complement the Looney theme).