For investigative travelers, all the world's a bookshelf

I'm pretty sure somebody did a study recently and discovered there are now more companies publishing guidebooks than there are people to read them.

OK, maybe they didn't. But sometimes it seems that way. Step to the travel section of your local bookshop and you'll hear the shelves groaning in 73 languages.

Along with Fodor and Frommer stand such new entrants as Eyewitness Top 10, a list-reliant series from DK Publishing that made its debut last year; and the Moon Metro series, which is part map, part guidebook.

It's impossible to keep up. Lonely Planet, the 800-pound gorilla of the trade, has nearly 700 titles in print and plans to introduce a national park series, beginning with Yosemite in March.

But after several years of field testing, a bookish traveler ends up with favorites. I've listed them here, along with tips from two veteran travel booksellers.

For sheer global reach and dogged research, attention must be paid to Lonely Planet, the Australia-based publisher that turns 30 this year. Born as a tip sheet from shoestring travelers in Asia, the company has grown to include nearly 700 titles and has been sidling ever closer to the middle of the road. Instead of focusing solely on backpackers, these days Lonely Planet covers bourgeois destinations it never used to, such as Las Vegas. As a traveler who's willing to spend more than $100 a night now and again if it means being comfortable, I'm all in favor.

Another good name to look for is Moon, a guidebook series that began the same year Lonely Planet did. Moon's writers are big believers in context, and the books are usually crowded with sidebar information that can add crucial perspective.

However, if someone ordered me to fly to Vienna tomorrow, I'd probably start by thumbing through one of the profusely illustrated city guides published under the DK Eyewitness and Knopf brands. (DK Eyewitness and Knopf aren't partners; both just happen to publish photo-laden, upscale-oriented books, taller than they are wide, on fancy paper.) For a visual introduction, they're hard to beat.

Then there are the specialty guidebooks, good for certain travelers but not necessarily for everybody. Blue Guides, based in England, are an example: They offer more detailed, reliable historical and architectural information than any other books I've encountered, but the writing is relatively dull, and eating and sleeping info isn't the priority.

For a South American trip, the South American Handbook has been the gold standard for more than 70 years. (These days it's part of a growing series known as Footprint Handbooks, again based in England.)

In the same specialist vein, Michelin's green guides are top-notch for elegant overall information, good maps and sound judgments on how much time a place is worth. The drawback: virtually no hotel information. (Yes, Michelin's red guides cover dining and lodgings. But little else.)

I have nothing against Frommer and Fodor, by the way; they're solid middle-of-the-road series. Rough Guides, which edge toward the budget end, are strong too. And the recently redesigned Access city guides (with their color-coded texts and neighborhood maps) continue to excel graphically.

Let's Go guides, the series begun by Harvard students and relaunched this year, seems to be reenergized as well.

But when you approach those travel bookshelves, there are pitfalls. For instance, always check the publication date. Depending on how fast the books sell, publishers have different cycles for new editions. If a guidebook is updated yearly, you can usually count on the publisher to brag about it by putting the year on the cover. (Frommer is especially bold about this.) If the updates are less frequent, that info is likely to be somewhere inside.

Second, follow the money. That is, unless the books explicitly state that the authors accepted no free services or discounts, assume they did. Publishers don't pay guidebook writers particularly well, and in many cases, the more freebies they can cadge, the more income they'll clear from the project. Many publishers make a point of saying they don't exchange positive mention for discounts or freebies, but that's not quite the same as saying you don't take those discounts and freebies.

Asked to rank guidebooks by sales, Priscilla Ulene, owner of the Traveler's Bookcase on West 3rd Street in Los Angeles, replies: "Lonely Planet is No. 1, and I would say DK Eyewitness is No. 2. And TimeOut is moving up." (TimeOut, which began as a London night life magazine, has been expanding its guidebook operations for several years.)

Ulene adds that her customers seem to prefer Fodor to Frommer and that many enjoy the year-old Moon Metro series of map-heavy city guides.

Like Ulene, Louanne Kalvinskas of Distant Lands bookshop on Raymond Avenue in Pasadena puts Lonely Planet and DK Eyewitness one-two in popularity among her customers. Lately she has noticed enthusiasm among Hawaiian travelers for the "Revealed" series ("Hawaii, the Big Island Revealed: The Ultimate Guidebook," and its siblings), published by Wizard Publications.

For a more individual touch, Kalvinskas also likes Sandra A. Gustafson's "Great Sleeps" and "Great Eats" series (which includes London, Paris, Rome, Venice and Florence and is published by Chronicle Books). The series used to be known as cheap sleeps and eats. Now Gustafson, who visits every listed location, has more room to maneuver in the marketplace.