I am looking for an overall dollar amount of the total sales in the
eBook/informational products marketplace (especially the sales of
business related eBooks). I am also seeking how many estimated
consumers are interested in or have purchased in this market. I am
*not* looking for information about eBook reading devices (hardware).
For example, go to http://www.ebookpak.com/, scroll half way down the
page, and look at the CommerceNet / Nielsen Media Research survey. It
shows how many people have purchased books and informational products
in 1999, but does not list a dollar amount or the overall worth/sales
of the market. Statistics compiled from any year within the last five
years will do, but the more recent the information, the better.

The latest "Ipsos Adult BookTrendsSM Update", an ongoing survey of
more than 12,000 nationally representative households, also showed
that print books represented 98 percent of all books bought, while
eBooks were only 0.1 percent. Less than one-half million eBooks were
purchased by consumers between January and June 2001, representing a
dollar volume of $5.3 million. This might be attributed to the fact
that the average price for an eBook was $17.60, while hard cover books
averaged $13.30 in price and paperbacks cost an average of $7.64.
Barrie Rappaport, spokesperson for Ipsos BookTrends, noted, "Last
summer’s Ipsos-NPD/NPD eVisory Report: 'The Online Book Market',"
clearly indicated that consumers did not expect to pay a lot for
eBooks."
http://www.ipsos-npd.com/about/news/01_1030.html

According to R. R. Bowker, sales from January to September 2001 were
40,618 with a total figure of $1,025,289.18 and $25.24 for an average
price. For business ebooks the figures were 380 books, $6,996.25
totalk income, and an average price of $18.41 per book.

United States eBook Sales Statistics
http://www.bookzone.com/services/stats.html

Google Search terms ebook sale statistics

I'll keep working on this as I have time.

Regards,
readersguide