Q: Could you recommend some books on statistics that would allow me to be more efficient at Business Analytics?

A: Below are some sites that you may find useful.

1)      The online copy of StatSoft, the Statistica textbook, a good resource, and it’s organized as a book.
http://www.statsoft.com/textbook/

2) UCLA has an online probability and statistics book, although it may be too elementary for you.
http://wiki.stat.ucla.edu/socr/index.php/Probability_and_statistics_EBook

3)      Planet Math has a lot of very useful links.   If you scroll down the page for the URL below, you’ll see a link labeled 62-XX, Statistics.  (There are plenty of other valuable links too.)
http://planetmath.org/msc_browser/

4)      The Kahn has some excellent short videos on specific topics in statistics.  More generally, the entire site is very well regarded.
http://www.khanacademy.org/#statistics

It you share the name(s) of the (text)book(s) that you’ve read I can identify which resources may be of the most use to you.  As I’m sure you’ve discovered, statistics fractures into a myriad of sub topics just like mathematics.  So narrowing this down will let me help you better.