Icehouse pyramids

Short Answer:
Your best bet may be to wait until October to get these. In the mean time, you could temporarily use the paper print-and-fold Piecepack Pyramids.

Long Answer:
I am a great fan of Looney labs and their games. The Icehouse Pieces (now being branded as Looney Pyramids) are a great gaming system with tons of games designed around them. (Checkout http://icehousegames.org/wiki/ for many free rules to some great games; mostly designed by fans.) Looney Labs other games such as the various Fluxx variations, Are you the Werewolf/Traitor, and Chrononauts/Back To The Future, etc games are also quite worthwhile.

Anyway, as far as availability of the pyramids...
Now is a very tough time to get them. Looney Labs has focused hard through the years to make all of their games here in the states, but recently they have financially been forced to start producing their pyramids overseas. However, they have hit a snag with the European Safety Testing (The pyramids from the new molds were deemed to be too pointy for safety; especially for children in the age 6+ group that they were testing for.) They did pass all Canadian and US safety tests however. But due to the EU testing, they were forced to rework some of their packaging for sales in North America. This delayed the release of the new pyramids until September 30th. (See the whole story here: http://www.looneylabs.com/OurGames/RetailerSupport/PyramidTesting.html)

When they start selling the pieces again (Sept 30th) they will be in the following formats: (http://www.looneypyramids.com)
IceDice: A Pyramid shaped bag containing two trios* each of Red, Yellow, Green, Blue, and Black pieces, plus two custom dice & rules for two games.
(*A trio is a set of one small, one medium, and one large pyramid of the same color.)
Looney Pyramids: (Rainbow & Xeno) A box containing one trio each of either Red, Yellow, Green, Blue, and Black pieces (Rainbow) or Purple, Orange, Cyan, Clear, and White (Xeno).
Treehouse: A (smaller) Pyramid shaped bag containing one trio of Red, Yellow, Green, Blue, and Black pieces, plus a custom die and rules for the game Treehouse.

To answer a couple more of your specific questions...
I highly doubt that you will be able to find any similar pyramids from other manufactureers. Unless you want to go to Crystal Caste (http://crystalcaste.com) and pay a fortune for some very nice stone pieces.
I also doubt that you would be able to find IceTowers (or Zendo) for $40 anywhere at this point. But at that price, I would say that they are worth it. (60 pyramids for $40 vs 15 for $12) However, you may just want to wait for the new pieces in October since they will be in a different color combination. (RYGBK vs RYGB). And there will probably be no good way to just get a set of 5 trios of Black pieces to round out your set.

I could probably go on and on about this topic, but for now, I will just say that if and when you do get some pieces, if you have any questions about Pyramid game recommendations, I may be able to help. Just let me know what types of games you normally like to play. Also let me know if you have any other specific questions about the pieces or specific games, and I will try to be more consise on those responces.