Keith, can you tell me who the top 10 best-selling female artists of all time, and how many records they have sold? Thanks, Martin W. Quinlan.

Hello Martin, that's an easy enough question. I assume you mean solo female artists, right? I can't use Nielsen SoundScan's figures for this list, as that company, which currently supplies the data that informs Billboard's sales charts, only began tabulating data in 1991. Thus, I am using the certification information from the Recording Industry Association of America (visit them at riaa.com). The organization bases its gold and platinum awards on the number of units shipped to retailers - in the United States; there is no one firm that keeps track of worldwide sales.
As you can see from the list below, Barbra Streisand is out in front with more than 70 million units. She's followed by Mariah Carey, whose recent double-platinum certification of "The Emancipation of Mimi" pushes her ahead of Madonna. Although, with Madonna, who is now No. 3, planning to release a new studio album later this year and Carey continuing to sell strongly, these numbers will most definitely change in a few months.
Here is the list of to top 10 female artists according to the RIAA:

01. Barbra Streisand (70.5 million)
02. Mariah Carey (63 million)
03. Madonna (61 million)
04. Whitney Houston (54 million)
05. (tie) Celine Dion (47 million)
(tie) Shania Twain (47 million)
07. Reba McEntire (36.5 million)
08. Britney Spears (31 million)
09. Linda Ronstadt (30 million)
10. Janet Jackson (25 million)

(Ask Billboard)