How many search engines are there?

There are 70,000. Most are specialized for one type of information.

There are three primary search engines today with varying degrees of popularity and market share -- Google (70%) Yahoo! (20%) Bing (10%). While there are hundreds of other secondary search engines available, most if not all of them pull their results from one or more of the big 3 above.

There are new search engines every day coming out.