Apple today unveiled the iTunes WiFi Music Store.

The store offers music buyers the ability to browse, search, preview, purchase and download songs and albums from the iTunes Music Store over a WiFi network directly onto their iPod touch or iPhone.

iTunes Once they connect their iPod touch or iPhone back to their PC or Mac, downloaded music will automatically sync back into their iTunes library. If users have only partially downloaded a song or album onto their iPod touch or iPhone, their computer will complete the download automatically. Prices and selection are the same as on the regular iTunes Store.

“The iTunes Wi-Fi Music Store is really fun - you can browse, search, freely preview, buy and instantly download music right onto your iPod touch or iPhone,” said Apple CEO, Steve Jobs.

“Innovative products like this keep iTunes at the forefront of the digital music revolution,” he added.

As reported elsewhere, iTunes customers can also create custom ringtones by selecting up to a 30-second segment from over a million participating songs on iTunes and easily sync them onto their iPhone.

Once a customer has purchased a participating song from iTunes, including previously purchased participating songs, it will only cost 99 cents to make up to a 30-second segment of that song into a ringtone and easily sync it onto their iPhone.

Customers can personalize their ringtones by choosing which portion of the song they want to use, and setting custom fade in and fade out points. iPhone users can assign a custom ringtone to be their default ringtone and they can also assign them to individual callers in their address book. Customers still have full use of the originally purchased song.

Apple today also released the next generation of the world’s most popular music and video jukebox, iTunes 7.4.

iTunes 7.4 includes a larger viewing area for movies and TV, filling the entire iTunes window. Users can also now rate entire albums as well as individual songs.

Both the new iTunes WiFi Music Store and custom iTunes ringtones for iPhone will be available later this month. iTunes 7.4 is available immediately as a free download.