May I suggest a gem of a book for addition to the "Best Books for Building a Small Home" list?
It is called "Workshop Math", by Robert Scharff.
http://www.amazon.com/Workshop-Math-Robert-Scharff/dp/0806958022/ref=sr_1_1?ie=UTF8&qid=1289342677&sr=8-1
Despite the title, this book is really about calculations involved in building a structure.
Here is the Table of Contents:
-- Math for Construction Layout and Estimating
-- Math for Rough Carpentry
-- Math for Interior Finishing
-- Math in the Shop
-- Basic Electrical Calculations
-- Math for Heating, Cooling, and Plumbing
-- Math for Energy Savings
Some of the reviews at the bottom of the Amazon page give a good indication of the quality. I found a copy at a yard sale. A nice surprise!