Amazon.com has posted first quarter net sales of $9.85bn, an increase of 38% compared to $7.13bn in the same period last year.

Operating income for the first quarter of 2011 decreased to $322m, compared to $394m for the same period last year.

Net income for the first quarter of 2011 was $201m or $0.44 per diluted share, compared to $299m or $0.66 per diluted share in the same quarter a year ago.

During the quarter, Amazon introduced a new member of the Kindle family; launched the largest eBookstore in Germany with over 650,000 titles, including more than 25,000 German-language books; and announced Amazon Cloud Drive, Amazon Cloud Player for Web and Amazon Cloud Player for Android.

Amazon.com founder and CEO Jeff Bezos said in the last 90 days, they announced Kindle with special offers, Kindle Library Lending, Audible audiobooks on Kindle, Appstore for Android, Amazon for Windows Phone 7, Checkout by Amazon in both Germany and UK., a Kindle Store in Germany, Cloud Drive, Cloud Player, and Prime Instant Video.

The company expects net sales to be in the range of $8.85bn and $9.65bn for Q2 2011.