Difference between The New Complete Book of Self-Sufficiency and The Self-Sufficient Life And How To

Does anyone know the two books:

The New Complete Book of Self-Sufficiency (9781405345101) http://www.bol.com/nl/p/the-new-complete-book-of-self-sufficiency/1001004006526692/
The Self-Sufficient Life And How To Live It (9780756654504) http://www.bol.com/nl/p/the-self-sufficient-life-and-how-to-live-it/1001004007107437/

Because it seems to me that both these books are on the same subject and I don't know which one is a newer version or better. Does anyone know these two books?

According to the links you provided, they are both by the same author, with a few page difference between them.
One was published in Aug 2009, and the other in Sept '09, but by different publishers.

Perhaps you could find them in a library, or book store to compare the two.

They could very well be the same thing, or, if different, I would imagine the bulk of the contents is 'mirror image' of the other.
I cannot imagine an author writing two different books on the same topic one month apart.

Each publisher probably chose titles that they believed best fit their intended audiences.
It seems strange that 2 publishers would print the same book, but each has their own marketing area.