Planning travel with the web is so helpful, you can almost skip the trip!

Lonely Planet was, and is, the gold standard for travel books. Want to know a $45 a night hotel in Paris that's safe and clean -- spend $25 on Lonely Planet Paris.

But, frankly, reading such a book is not a very rich experience. You can't really tell if your wife would prefer Paris' Marais district over Saint Germain des pres. And you have no idea whether the information is up to date.

Flickr & Youtube
Today, I still plan travel with a Lonely Planet guide, but I go beyond. The photo management site Flickr, sold as a tool to store and share photos, doubles as tagged photographic evidence of everything on Earth. Want to see an Andalucian Villa? Do a Flickr search. The key I've found is to search for both a place name and an activity. Searching for "paris" is too general. Do "Paris" and "Shopping" or "Seville" and "yelling." If you're going outside the tourist season (when most photos are taken), throw in a month or season name. Before booking a hotel room, search for that ... most often than not, I've found one person has taken the obligatory room and window shots.

Flickr is enjoyed by photo snobs, so there are plenty of beautiful shots. Not so much with youtube. But by searching for videos taken within a town or street -- even if they're of two kids doing skateboard tricks -- instantly immerses you in the overseas environment. Seeing the action can make what is at first foreign come to be natural.
These guys seemed to get very smart in the past year -- or, like fax machines, they only became useful after they become popular. Either way, it seems that even the most remote hotel is now reviewed by multiple people, with detailed written reviews, a quantitative survey and even, occasioannly, amateur photographs. In many cases, by reading individual reviews, you can reconcile wildly different review scores. For example, one person may give a hotel 5 stars and comment that it was very clean and friendly, while another would give it 2 stars and add that the towels were sub-par and it room service was slow; the first person may have splurged on a rare, nice hotel, whereas the latter may be used to extravagance and found this place lacking.

Expedia also has hotel reviews, and I believe they are tied to actual reservations made through Expedia, so they're much more likely to be authentic -- that said, as a writer, I like to think I can spot a bullshit review.

Booking and other sites often have very good special prices. They key here is to check every day for weeks in advance of a trip. Furthermore, it's worth it to call the hotel to confirm the reservation within a few hours of making it through one of these sites.

Finally, if I can't find some information anywhere else, I use Yahoo Answers. Here I can post a question and categorize it narrowly -- often, within 2-3 hours I have multiple responses. Typical questions may be: how much is a taxi from XX airport to the centre of town.