There are many kinds of books available on various aspects of personal development in the market. Have an idea that which kind of book you are looking for and which areas are you looking to concentrate on. Search the books as per your requirements and make a list of these books.
Make sure that you check feedback from the readers on various books on personal development. You can check this out with friends as well as online so that you know that the book you are going to buy indeed offers some good advice and is not a low standard one. Not everyone will like the same book but you can have an idea from the reviews whether the book is a good read or not.
Once you have an idea which book or books you want, check them out at the local book store. Ask the staff at the store which books are more in demand and which ones are better in their opinions to other ones. Once you have the idea, you can get the book or books of your liking.