The only problem with this list is it includes both free fonts and licensed fonts where you need to pay to use it on commercial products like book covers. Of course, if the font strikes your fancy and you're willing to buy a license, go for it, but I'm cheap. So I spent an hour on Google and identified only twenty of the fonts that are in the public domain. Here they are. Click on the font names to find the fonts. If the link is broken, use Google:
Liberation Sans (I couldn't find a version that looked like the one in the picture, though)
The way this works is, look at the image to find a font you want, and then check the list to see if it's free. Or vice versa. A quick Google search for the font name will usually get you plenty of websites where you can download and start using them to make beautiful covers.
UPDATE: I was reluctant to include links, because things on the Internet change so much, but I decided to go ahead and do it.
Which font would you use?
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