I am privately contracting my new home. I have seen a 'slight' increase in price of wood materials, but other items that can be affected by petroleum (shingles, etc) have not spiked as much as I thought, if any.
I work in an industry that deals with different types of clients. One is wood products (lumber, paper, particle board, etc). I attribute the lack of spiked prices due to the over abundance of stock they had on hand at the time.
In this area (NC), there has been no shortage I am aware of, and prices have only been affected by psychology, not shortages.
Personally, I would attribute the drop in demand to a number of things; interest rates, home prices (ridiculous in Cary), and the psychological impact of being told that any day you could/would lose your job. I can only hope that my house in Cary will sell since it is so much cheaper than anything built in the last few years.
My builder (we just bought a new home) said he hasn't seen the spike either, but he expects it.