Last.fm’s mobile application for the iPhone and iPod touch is now officially available for download. To get started, go to the music category of the iTunes App store (in iTunes or on your iPhone/Touch). Find the Last.fm app and download it (for free).

Last.fm is launching the application in a limited number of markets. As quoted from the Last.fm Blog: “…we are initially rolling this out in the US, UK, Canada, France, Germany and Spain. We’re looking at other locales but have to deal with licensing and a host of other issues. We assure you that we’re working on it.”

Listen to free streaming radio on your iPhone with Last.fm. It also allows you to listen to your favorite artists, discover new music, and share music with the friends in your iPhone contact list.

Based on your music taste, Last.fm creates radio stations from its 5 million + track music catalog. You can start a radio station by entering any artist name or genre and listen for hours; all without having to store any music on your iPhone. Additionally, you can check out artist bios, similar artists and concert info.