If you're looking to use tarot as a purely divinatory tool, then I would recommend '78 Degrees of Wisdom' and its sequel. The first covers the Major Arcana, in a decent amount of depth. Its sequel, same title with a 'Part 2' tagged on, covers the Minor Arcana.
I would also recommend exploring introductory lessons online, from many sources. One person's opinion might not work for you as well as it does for them. Reading tarot falls somewhere between reading the symbolism on the card from a list method (such as the Death card means change, or the end of an era) and intuitively (what a card 'feels' like it means in a given situation).