Since the advent of the Google and Yahoo (and more recently Virtual Earth) mapping APIs there are hundreds of developers and entrepreneurs who have built interesting and useful mashups. But how does one find them? Of course you could search on Google, Yahoo or Microsoft Live or look at some of the worthy blogs devoted to mapping such as Google Maps Mania or The Map Room.

But you could also search Mapshark, pointed out to us by Philipp Lenssen. According to Philipp’s post the site was created by Alaska attorney Andrew Mitton, who says he’s only spent $100 on the site (plus his time: $350 per hour?). It was built using Google’s Custom Search Engine.

Not all the sites in the index are equally map centric or equally relevant to your query, but there’s lots of interesting stuff here to be discovered. Here are a few examples at random:

Travel in Nepal New York Bars Bike Trails in Marin County (CA) Best Wedding Locations Seattle Biodiesel Stations

Because it’s the Google CSE, it also features Google tools such as “did you mean” as well as Google sponsored links.

Ideally, some sort of preview or other image tool would be useful to see whether the particular site had the desired information/maps. And, as you start to look through them, you find that the relevance and quality of the results can vary dramatically. But Mapshark is a tool that can be used to discover mashups and information you might never have known about otherwise.

Related Topics: Google: APIs | Google: Maps & Local | Microsoft: Bing Maps & Local | Search Engines: Maps & Local Search Engines | Yahoo: Maps & Local

About The Author: Greg Sterling is a Contributing Editor at Search Engine Land. He writes a personal blog Screenwerk, about SoLoMo issues and connecting the dots between online and offline. He also posts at Internet2Go, which is focused on the mobile Internet. Follow him @gsterling. See more articles by Greg Sterling