It's impossible for a single guidebook to completely cover a country as massive and diverse as America, but Frommer's USA comes close. Sure, some will quibble with destination choices (for example, the editors mention Martha's Vineyard, but not Nantucket) but overall, this 1,000-plus-page tome hits the mark. Chapters focus on both major cities and larger regions (New England, Southern California, etc.), covering such basics as activities, lodging, and affordable restaurants, and doing so in excruciating detail (admission prices, hours of operation, directions, whether or not a hotel has valet parking). You'll also find plenty of full-page maps and quirky little sidebars (gourmet food stores in Napa, best Chicago blues bars). As if that weren't enough, there's an online travel directory with Web addresses for everything from Ticketmaster to Zagat's to Amtrak. If you plan on seeing even a sliver of what this country has to offer, take this guidebook with you.