There are several ways to check coverage. This is your one-stop-blog, putting all links at your fingertips. Below are links to website pages for those interested in checking 3G/4G, voice, data, roaming and recent cell site growth. In addition, there are helpful tips, how parental controls and roaming work, types of searches available and how to check email in another country, to name a few. Check it out
Located on sprint.com is an international roaming hub of information. The page includes traveling with a Nextel or Sprint device as well as travel tips on your destination and the phone you're taking.
An overall link to coverage across the US. It is broken down by a city drop down or city/state/zip code which can be typed into the search engine. These can then be parced for additional detail by type of coverage.
The international coverage areas across the world are located through a targeted search at this link.
Here are the devices which are capable of international roaming.