For tarot divination, I've often seen the book '78 Degrees of Wisdom' (a two-book series) recommended. The first focuses on the major arcana, while the second focuses on the remainder.
I'd also suggest, perhaps, a book or two about the occult imagery in the cards. It can give a lot of insight into the specifics of the art itself.
I did buy a book about introductory pendulum use a while back, and while it did have some good parts, there was also some questionable content. I'm still considering a few options.
For scrying, I have read a few briefings, mostly in pdf, which I have found interesting. I haven't actually tried the method much, but do plan to delve in at some future point as well.
And with all of your mentioned methods of divination, there are some public domain resources, mostly available as pdf documents. But as always, whatever you read, do so carefully and filter it according to your own beliefs.
Some advice from my limited experience with divination:
Reading about yourself -- especially with a pendulum -- can skew the results, as you may have a response more of your hopes than of an answer.
Tarot is a guide, and not a prediction of the future; it shows but a possibility. Runes are similar in that aspect. Tarot is not so great for yes-no answers, but changing a "should I" to a "what would happen if I" question may get a better answer. "Does he love me" may be better asked of the cards, "How does he feel about me?"
While a pendulum on its own may be used for yes-no answers, it can also be used for relative "how much" types of questions. There is also the option of making a divination board, and there is no limit to a layout for one. An image search online will reveal loads of types. Since a pendulum is an interesting link to the subconscious, and I have read that the subconscious acts more in symbols and concepts rather than in literal spellings and quantities, the divination boards I have made deal more with such things. But there are some people who successfully use some very intricate divination boards.
Scrying is something I find very interesting. It relies on depriving the brain of mental stimuli. When the visual cortex is under-stimulated, sometimes the brain may fire off random bits of information trying to see if the eyes are working right. This is the literal source of some of the visualizations. It's basically a self-induced hallucination, though not in the sense of needing professional help. I forget the exact term, however. It is the same phenomenon which happens when someone stares at their own reflection until they no longer recognize themselves, and the image may even distort. That said, these images are also the source of the divination.