Start your journey to Mexico by doing some research. It's a large and diverse country, where you can travel cheaply or expensively -- that's up to you. Either way, gaining a bit of knowledge ahead of time can save you time, money, and regrets. The books below all cover the entire country. After you decide on a destination, consider purchasing a guide dedicated to the region you will visit.
Advocate for the budget traveler, Frommer's helps readers avoid tourist traps. The front features evocative color photos, and they're followed by "best of" picks -- beaches, archeological sites, adventure vacations, and much more. The rest of the book focuses on different regions. Frommer's is updated annually (unlike some others), which makes it a trustworthy guide.
I'm a huge fan of the Eyewitness Travel Guides. They don't only tell you about places, they show you, with superlative photography and helpful drawings of places you won't want to miss on your travels.
If you're considering your first Mexico vacation, this travel guide will help to steer you in the right direction, to a place where you will be comfortable and within your budget.
Gorgeous four-color pictures on nearly every page, and text with an historical bent make this book a leisurely read.
The VW Beetle of travel guides, Lonely Planet guides give you the essentials, but I've never found them particularly compelling to read. Still, if you're traveling on a strict budget, you may want to rely on this one.