Does anyone know of a service/db I can use for businesses and geocode?

Question

I was wondering how and where companies like Foursquare/Gowalla find and keep up to date their list of location/businesses.

Is it a web service? Do they buy a directory and enter it into a database?

Answer 1

Google has a geocoding service that's freely available for personal use.

For business use, it costs a few$, but it's still pretty reasonable.

And the API is pretty straightforward

http://code.google.com/apis/maps/documentation/javascript/v2/services.html

Answer 2

This is from a comment I found at http://www.quora.com/Where-or-how-does-a-company-like-Foursquare-get-a-directory-of-all-locations-and-their-addresses

Companies usually get place data from one of the following: Data licenses: Companies like Localeze, InfoUSA, Amacai etc. license location data: Big players like TeleAtlas and Navteq serve as global aggregators of this data. There are also lots of small niche players that license e.g. restaurant data only, or ATM data only, on a per country basis. Crowd Sourcing. Some companies crowd source their data. Open Data Sets. There are some data sets with a creative commons or other license from which location related data can be extracted. E.g. GeoCommons and Wikipedia. APIs. A number of companies provides APIs by which you can access data on the fly. This include GeoAPI.com, Google, Yelp and others. In general, this data is fragmented both in type (e.g. POI vs neighborhood or geocode) and place (US vs UK vs South Africa vs Wherever)