Amazon launched the Kindle Owners Lending Library back in November, 2011. Available to Amazon Prime members to borrow for free, the library is a huge boon for self-published authors, or as Amazon styles them, “Kindle Direct Publishing” (KDP) authors.

Basically, independent “self-published” authors sign the digital rights to their book for a contract period with Amazon. They keep the paper publishing rights, but cannot distribute their book electronically anywhere else – not even their own website – for the duration of the contract. But, the benefits from Amazon’s KDP program are handsome nowadays.

From Amazon’s KDP Select FAQ:

“Your share of the Kindle Owners’ Lending Library Fund is calculated based on a share of the total number of qualified borrows of all participating KDP titles. For example, if the monthly fund amount is $500,000, the total qualified borrows of all participating KDP titles is 100,000, and your book was borrowed 1,500 times, you will earn 1.5% (1,500/100,000 = 1.5%), or $7,500 for that month.”

Amazon announced today that the library has over 75,000 books, and that they have increased the fund pool total from $500,000 to $700,000.

For those authors who rank in the top tier of borrowed books, those numbers can be sweet. Amazon announced these examples of KDP author earnings from the program:

* Carolyn McCray, a writer of paranormal romance novels, historical thrillers and mysteries, earned $8,250 from the KDP Select fund in December.

* Rachel Yu is a 16-year-old author of children’s books, and she earned $6,200 from the KDP Select fund in the month of December.

* The Grabarchuk family earned $6,300 from the KDP Select fund in December from their puzzle books.

* Amber Scott is a romance writer and earned $7,650 from the KDP Select fund in December.

Amazon says it will add at least $6 million to the KDP fund in 2010.