It’s been months since Amazon signed its monumental deal with the “big four” music labels Sony BMG, Universal, Warner and EMI - potentially changing the way music is sold forever. According to TechCrunch.com, digital music sales account for 15 percent of the total music market globally and 30 percent of sales in the U.S . The availability of legal DRM-free music across the Internet is growing larger and stronger. More music stores are breaking away from DRMmusic; however, some have yet to move to a completely DRM-free mode.

Here is a brief glance at which online music stores are sticking to their guns and those moving to a strictly MP3 model:

Completely DRM

Yahoo! Jukebox – Music downloaded through Yahoo! is only available in WMA. It doesn’t look like they have any plans to change to DRM-free downloads anytime in the near future.

Zune Marketplace – Music bought from the Zune Marketplace is sold in WMA format, but includes a DRM encryption specifically for Zune players. Music from the Zune Marketplace will not play on any other media player and it doesn’t look like Microsoft has any plans to change this.

BuyMusic@ Buy.com – BuyMusic is a small online music store with only about one million tracks available. Songs are only available in WMA. Although they have some great prices they are encrypted with the same DRM as Napster and Yahoo!

Some DRM

iTunes – Originally iTunes only offered songs in DRM “FairPlay” ACC format ( M4P extension), but for years they were in negotiations with the music labels to get DRM-free licensing. Little by little Apple chipped away at the labels and eventually managed to work some deals. Now, about half of the iTunes library is DRM-free; however, they are still in AAC format and will only work with iPod and a few select players from other manufacturers.

Rhapsody – “Helix” is Rhapsody’s proprietary DRM encryption. Purchasing tracks from Rhapsody can be confusing as far as file formats go. Tracks downloaded in Rhapsody are natively in .RAX or .RA (Rhapsody’s own version of AAC) or the media manager can be configured to WMA. The selection of DRM-free tracks are available in MP3. There are only about one million songs on Rhapsody that are currently DRM-free.

Napster – Although their individually purchased tracks are DRM-free, the music attached to their subscription service is only available in DRMed WMA.

Puretracks – A smaller, lesser known music download site, Puretracks simply offers songs in both protected WMA and open MP3 format. Most songs are only available in a DRM format, but if there is a MP3 option it is clearly listed. There is also a tab at the top of the webpage for MP3 files, but again the selection is small.

DRM-free

Napster – The most recent music download service to dump DRM, Napster is considered the grandfather of music download sites, the first P2P network to go legit. Individual MP3 tracks bought through Napster are completely DRM-free. Napster now has the largest selection of DRM-free MP3s.

Amazon MP3 – The first company to sign a deal with all the major music labels to sell completely DRM-free music. Currently, there are more than three million songs available on Amazon MP3 and it is quickly becoming an iTune competitor by selling songs strictly in MP3 format (making it compatible with all media players) and at a higher bitrate.

Wal-Mart – In an unusual move, Wal-Mart completely dropped all their DRM sponsored WMA tracks and only sells MP3 files and they are cheaper than iTunes and Amazon MP3.

eMusic – A subscription based music download store eMusic features songs from mostly independent artists. For $9.99 a month you can download 40 songs all in MP3 format. Unlike other subscription services there are no limitations on these tracks. Once downloaded they are yours.

Audio Lunchbox – Another music download site that features indie artists. Audio Lunchbox does not have contracts with any major music labels so selection is limited but all tracks are in MP3 format.

The data suggests that online music stores are only getting stronger and with many offering DRM-free music, it seems that the consumer might have a small win against the music moguls in the near future.

If you need a new MP3 player to play your music on, check out our review of MP3 Players, where you can find rankings of the best MP3 players on the market.