(AP) -- Fans of band-simulation games such as "Guitar Hero" and "Rock Band" have few excuses not to seek out legitimate sheet music these days if they hope to graduate to playing real guitars.
A growing number of websites may help reverse a decline in sheet music sales last year. Trade magazine Music Trades, which compiles sales data, showed it was the first drop in eight years.
The most popular site is Ultimate-Guitar.com, which was founded by a Russian student in 1998. It offers guitar tablatures for popular songs - shorthands for explaining where your fingers go on a fret board, as transcribed by the site's users.
The site became a pariah of music publishers, which claimed the site had no permission to post transcriptions to their songwriters' music, even though some were inaccurate.
Even inaccurate transcriptions require licenses, an easily misunderstood concept that may have slowed Ultimate Guitar's path to legitimacy, said Jonathan Kehl, who handles licensing and business development for the company. In recent years, the site has obtained numerous licenses from music publishers including Sony/ATV, EMI and Alfred Music Publishing.
The site lets visitors, mostly amateurs, submit guitar tabs. These are then ranked and sometimes improved upon by other users. The site is free and shows ads to its more than 10 million visitors per month worldwide. The site, based in San Francisco, shares ad revenue with publishers to ensure that songwriters get paid, although Kehl didn't say how much.
"We're wearing the white cowboy hats now," Kehl said.
Other sites offer professionally produced transcriptions for download for 99 cents to more than $5. Among them: MusicNotes.com, GuitarInstructor.com and SheetMusicDirect.com.
UnitedWeTab.com, which launched in April, has put nearly 40 musicians to work transcribing songs, checking their accuracy with music publishers and making videos. The tabs sell for at least 99 cents each. The site's catalog has grown 15 percent since its launch and now boasts 14,000 songs, including ones transcribed by music publisher Hal Leonard Corp.
It takes two or three musicians about five days to get each new song right. UnitedWeTab's chief executive, Todd Gilman, said that makes the price of professional content worth it.
"We're giving people no excuse," he said. "You can actually get the songs you want, it's extremely accurate, and more importantly, especially for some of our younger users, it's cheap."
Explore further: 'Map spam' puts Google in awkward place