If you are looking for a general intro to TA then you could do a lot worse than buy this book. It is written in a very engaging conversational style (but not full of irrelevancies or padding). At the same time it is well structured and so can be used as a reference. Not all topics are covered in detail but tells you enough about each to help you decide if you want to buy further reading in that particular area.
I've just looked at Amazon and see it is the 3rd best selling book on TA, out of 710 - 'nuff said.