If your interest lies in baking or cooking, America's Test Kitchen puts out a wealth of tested and reliable recipes. This was my first source of information when I started to get really serious about pastry baking. I highly reccomend both of these books. There is some overlap between the two - if you think baking is your sole interest, then Baking Illustrated would be my suggestion. But Best Recipe has a huge selection of traditional cooking technique and recipes in addition to the baking sections.
America's Test Kitchen is also behind a number of magazines, including Cook's Illustrated as well as Cook's Country. I would suggest checking them out as well - if you prefer an e-solution, thier website offers access to a wide range of recipes as well, for a small subscription price.
This book is as classic as it gets and should be on the shelf of any serious baker. There are a ton of great recipes here as well as good reliable advice regarding technique and equipment. The recipes are very accessable and offers a nice balance of simple recipes with more sophisticated.
If your interests aim more towards cake, the equivelant book is also available. As of now, I don't have any content on the website regarding cake so if that is what you are looking for, this book comes highly recommended.
This is actually a textbook so there are a number of class related exercises and discussion topics but the information presented is very helpful. It delves into the science of baking and gives understandable insight into a complex subject.