Oodle is one of the web’s most popular classified search engines. Instead of searching one site’s classifieds, Oodle compiles classifieds from throughout the country’s online and print media and puts them all in one place. It claims to be the world’s largest “classified aggregator.”

Founded in 2004 by three ex-Excite.com executives, Oodle reaches approximately 3.5 million visitors per month with a global reach of over 30 million page views. Demographically, males are as likely to visit Oodle as females, and almost all visitors (90%) are 18 or older. Oodle tends to attract a lower income user (47% earn less than $60,000 per year), and those with little or no college education (46%).

Using Oodle is extremely easy as it categories its classified ads into several large categories: Cars, Real Estate, For Rent, Jobs, Pets, Tickets, Personals, Services, etc. Within each of these categories, you can search on several pieces of data. For instance, by clicking on “Real Estate”, you can search by type of home, state, or zip code. Listings will appear, which can be sorted by price, posted date, or best match.