Here are Directions to build one of our deer blinds. Since building these in the field can be difficult, I have taken to building the floor and four walls in panels in a location where I have access to electricity, then taking the floor and walls out to the field on the back of a pick up truck.
Depending on where you live, you can save a lot of money on materials by using stuff that lumber mills cast off as seconds or scrap. In northern Michigan we have several local lumber mills that have piles of this stuff that they would sell me for $20 per pick up truck load. With exception of the OSB, I have found that I can buld a blind with about 1 1/2 pickup loads of lumber.
I have also built whole blinds out of scrap scaffolding boards that were no longer OSHA approved.
In Texas, I have found free OSB available at feed stores. The OSB comes as dividers on pallets of SmartLik. The local Habitat resale store is a good source for building materials, especially shingles and office chairs.