There is a growing number of sources for free or economic loan or purchase of eBooks for reading on your laptop or tablet.
If you want to read a short preview, try these alternatives:
Hampshire Library When you select an eBook, there is normally a short sample, usually the first chapter (below the cover picture) which you can read online.
Southampton Library Click on eBook Catalogue (under Find Information). Then you can do a Quick Search or an Advanced Search.
Or click here, choose eBooks, decide if you want to Show only available titles, choose which grouping or Category you want, or pick a Featured book to Preview and/or Borrow..The previews do not work on all platforms.
Amazon Kindle eBooks. You can search for a book, read Product Description and Reviews, look inside to read introductory sections, and even occasionally get offered a free sample to download.
GoodReads list same eBooks where you can download or read excerpts or complete eBooks.
Open Culture 800 free audio books and much more.
Project Gutenberg Over 42,000 free eBooks.
I use Calibre (free on Mac and PC) to view eBooks from other sources on computer and convert them between formats, e.g. Kindle AZW or Mobi <> ePub.
Then I copy them onto my Playbook (Blackberry) and/or Pat's Nexus 7 (Android), where we have been evaluating Aldiko, Amazon Kindle, FBReader (current favourite) and OneClickBook (for library loans). It's really down to individual preference: some let you override automatic switching between portrait and landscape, handy if you hold your tablet at an angle; others sync between tablets, computers and the cloud.
I try to standardise on the ePub format for maximum compatibility (apart from Kindle).