Ask HN: IS there a site about business models?

Derek Sivers speaking about business and profit models:

http://b.lesseverything.com/2010/2/3/derek-sivers-speaks-at-...

This is a great talk by Derek, I highly recommend it.

I bought the book he mentions in the talk, "Art of profitability", recommended.

I would be very interested on analyzing the business model of Amazon, Google, or even newer sites like Groupon.

This can be a beast, but Porter's work on 5 forces is really illuminating. If you do the hard work, you'll have a really good understanding of where your business fits in the larger context.

"business model generation" is a really good book on the subject: http://www.businessmodelgeneration.com/

Innovation and Entrepreneurship by Peter Drucker is a timeless book that I would suggest reading.