These are simply two of my favourite books concerning all of the outdoor skills which I am interested in. I would seriously recommend buying them as they do not simply repeat information which is available in 100 other books but offer new ideas and projects such as throwing sticks and bone tools along with the simplest methods of flint knapping.
They take a very realistic view on both long term and immediate projects and cover a very wide range as you can see here and here.
A lot of similar information is available either through the website of the SPT primitive.org or through primitiveways.
I looked at joining the SPT but I feel that international membership is not that great value for only 2 bulletins a year. These books however are a must buy!