Where do you get your textbooks for the iPad?

I want to get an iPad for college textbooks. Where do you get your textbooks for the iPad? Do you rent or buy them?Where do you get your textbooks for the iPad?
You can buy them from iTunesU or buy the soft copy of the book and download it into your iPad. iBook is avoid app to read PDFs and soft copy textbook.Where do you get your textbooks for the iPad?
There are a number of companies selling eTextbooks. Most of them provide a reader that runs on a iPad. So what you are looking for is not textbooks for an iPad but textbooks that come with a iPad reader. An example is there is a Kindle reader for the iPad which lets you get ebooks from amazon. Unfortunatly the availability of eTextbooks is limited as this article shows: http://ow.ly/6kcrv

It is good to use a price comparison site as it will show the availability and price of ebooks saving you a lot of time.