Ebay! Lots of used books on there cheap, $4-10 is usually what I pay. I look at reviews on Amazon or whatever and then go to ebay to buy them. Check farm and garden stores at the end of season, they'll Mark them down significantly sometimes.

Country wisdom and know how is a good one.

Look for organic gardening books, being self sufficient means not relying on pesticides most of the time. Better for you too.

Chickens are super easy, basically you just feed them and protect them from predators. They should have a coup, but mine sleep pretty much everywhere but the coup.

Look into mini cows, they produce more meat/milk per pound of feed than the full size versions.

Find other farmers in your area. One, they'll have a lot of good advice for growing in your specific part of the country. Two, you can barter. Trying to keep up a garden, chase down run away chickens, put out hay for cows, keep up fencing, it's a ton of work. Easier to have lots of cows or chickens and a garden, then trade/sell.

Consider growing or raising some specialty things. Mini cows are really popular, or certain breeds of chickens. Lemon cucumbers, or black tomatoes. People will pay a premium for that kind of stuff.

Finally, learn about tractors. They are essential. Plowing a garden plot, putting out hay, bush hogging, getting a truck out of the mud, pulling down a dead tree, it's endless really. Find an older model and learn how to care for it yourself. They'll last forever if you know what your doing.