You can check with the Recording Industry Association of America. (
http://www.riaa.com/) Although, much of the information and market data found there isn't nearly as accessible or entertaining as these next two sites.
The Best Selling Albums of All-Time. (
http://hometown.aol.com/PaulHry/music/riaa.html/) Updated monthly, so check back regularly.
And, Evergreens, (
http://www.airwindows.com/analysis/Evergreens.html/) “a study of RIAA record sales over the entire history of platinum albums.” A site with very interesting analysis based on freely available RIAA market data of long-term album sales. It makes for some fascinating reading. Just plan on spending part of a leisurely afternoon reading it; it's relatively lengthy and detailed.
So, as of today, the actual all-time record sales in America:
1. Eagles: Their Greatest Hits Asylum | 1976 (27 million sales)
2. Michael Jackson: Thriller Epic | December 1982 (26 million sales)
3. Pink Floyd: The Wall Columbia | 1979 (23 million sales)
4. Led Zeppelin: Untitled (IV) Atlantic | 1971 (22 million sales)
5. Billy Joel: Greatest Hits Volume I & II Columbia | 1985 (21 million sales)
6. AC/DC: Back in Black Atlantic | 1980 (19 million sales)
7. The Beatles: The Beatles [White Album] Apple | 1968 (18 million sales)
8. Fleetwood Mac: Rumours Reprise | 1977 (18 million sales)
9. Shania Twain: Come on Over Mercury Nashville | 1997 (16 million sales)
10. Whitney Houston & Various Artists: The Bodyguard Arista | 1992 (16 mill. sales)
11. Boston: Boston Epic | 1976 (16 million sales)
And based on Evergreen’s (
http://www.airwindows.com/analysis/Evergreens.html/) analysis, the Top 10 Commercially Important Albums of All-Time:
675 Eagles, Eagles Greatest Hits
660 Led Zeppelin, Led Zeppelin IV
594 The Beatles, The Beatles (White Album)
506 Pink Floyd, The Wall
494 Michael Jackson, Thriller
432 Fleetwood Mac, Rumours
420 The Beatles, The Beatles 1967-1970
420 Pink Floyd, Dark Side of the Moon
405 Elton John, Greatest Hits
400 Boston, Boston
As well, the Top 10 Commercially Important Artist Careers':
4129 The Beatles
2625 Led Zeppelin
2328 Hollywood Movie Soundtracks
2262 Elvis Presley
1759 Various (collections/label promo)
1508 Eagles
1453 Pink Floyd
1381 Billy Joel
1311 Elton John
1154 Barbra Streisand
Josh