With 8 out of 10 perspective home buyers already starting their searches online, Web 2.0 sites like Trulia.com are busy finding new ways to deliver real-time real estate information. Search the site's more than 2 million homes for sale. Here's the neat part: results are delivered "mash-up" style, with current listings (including full addresses) plotted on Google Maps. You can also sign up for "Trulia Alerts" to get an e-mail heads up the minute your dream home or fixer-upper fantasy hits the market.