Sounds cool?! Check out:

However i suggest you also look elsewhere. Anything on "sustainable building" will usually make an interesting read. If you really want to go the DIY/cheap method i suggest NOT hiring any companies but reading up a lot so you find what out what you like and what will work for you. You can't go wrong by ordering Mike Oehler's classic: 'The $50 & Up Underground House Book' and by studying material on Cob and Strawbale building.
The best place to order Oehler's book is:

Over the years i've looked into this topic quite a lot, so perhaps i will add more to this article in the future.