The Book Cover Archive is a thorough and expansive collection of book covers. You can browse the archive by designer, illustrator and publication. It even tells you what typefaces are used on the covers - very useful. Here you can find all of the Great Ideas/Loves series by David Pearson as well at the 70 commemerative covers by Penguin. There is a broad selection of both illustrative and typographic book cover design - all have been carefully selected and represent the best there is to offer! It's well worth a look. Here are just a few that I found - I particularly liked a series of Nabocov books published by Vintage.