There are plenty of apps that find restaurants, hospitals and other things near you using the iPhone's GPS. Localscope, a US$1.99 app, is the most complete and easy to use solution I've seen.
Localscope easily lets you find destinations using Google or Bing, Foursquare, Twitter and Wikimapia. You don't have to re-enter your search terms, just slide from one search engine to another. One side benefit was that in my area of Southern Arizona, Google had far more information than Bing. The app makes it easy to compare search results.
You can also search using your contacts or recent searches. Results can be viewed as a list, on a map, or using augmented reality, which is basically a live camera view with the direction of destinations superimposed on the screen. Phone numbers of destinations are provided, as well as websites for more info. A really nice feature is integration with both TomTom and Navigon apps. When you find a location, a tap on a button sends the data to those apps. Another tap, and you are navigating with turn-by-turn directions. I also like the ability to save a location to your address book or share a location via email, SMS, Twitter or Facebook.
Using the app was a pleasure, with the GUI nicely designed and easy to use. I really liked the specificity of catagories, like Barber, Gym and Ice Cream. Most apps don't drill down that far. Localscope is not US-centric, so it can be used anywhere. Integration with Navigon worked just fine for me. Localscope launched the Navigon app, and pushing one button started the route.
There are certainly a lot of free apps that do what Localscope does; for example, I have always liked Around Me. On the other hand, Localscope adds a lot of nice features, is ad free, utilizes multiple search engines, and integrates with two of the best-selling nav apps. I think Localscope is worthy of serious consideration. The app requires iOS 4.0 or greater.