My first wheel was successfully completed with nothing more than Sheldon's how-to, a tension meter and spoke wrench.

I have Brandt and Schraners' books. They both work fine.

The second purchase I would recommend a new wheel builder make, after a spoke wrench, is a Park TM-1 tension meter. Using it in combination with Park's TCC spreadsheet will do wonders for the uniform tension of your spokes and subsequent durability of your wheels.