How deep do you want to go? There's hobbyist books like Forrest Mims's classic "Getting Started in Electronics" or the more recent "Practical Electronics For I

How deep do you want to go? There's hobbyist books like Forrest Mims's classic "Getting Started in Electronics" or the more recent "Practical Electronics For Inventors". For a more in-depth treatment, you might take a look at Horowitz and Hill's "Art of Electronics".