You may not need a book, a video or a lesson to learn - althought all of those can help. If you think about finger pickin' as a basic pinching motion; between yer thumb and index finger - you' got the basics down. It sounds too simple, but it really is the basic motion. Yer thumb hits the bass and yer index finger plucks the string/s. A simple chord progression for say Steven Still's "Helplessly Hoping" gives you an easy first target for developing a finger style; it's easy to hear what strings to pick, and easy to finger pick with two fingers. Once you're comfortable with two, and yer middle finger to the mix, and maybe yer fourth. This style probably requires you anchor your hand against the pick guard with your ring finger. Ultimately, you can pick out bass, chords and melodies with three picking fingers, and use your middle finger to brush for percussion or accent.

Try it. Experiment. You can learn a lot on your own!