I have no idea about cystal balls, they dont take my fancy much! But tarot takes a long time to learn, in fact i doubt you ever finish learning. I have read for 13 years now and still get times where a reading isnt particularly clear.
What deck of cards do you have? The rider-waite deck is great for newcomers to the tarot, its imagery contains a lot of clues to the basic meanings, rather than having to refer to a book.
When you take out a card, just look at it, see what comes to mind. What colours are used? What words can you associate with the imagery? If you do this BEFORE looking for meanings in a book, you should notice you can grasp at least some of it by yourself.
The books will only teach you a very basic meaning, to properly read the cards, you need to look at other cards in the spread, how they relate to your card, where your card is positioned in a spread and much more. Its really quite complex, so it might be better to just focus on the tarot OR the crystal ball, rather than them both?
Where you keep your cards...I dont keep them on my person, i keep them where i spend the most time in my house (my personal space). Shamefully its at my computer! So they are in a special box beside my printer.
Good luck