I've given away so many writing prompt books in my lifetime. None of them ever matched what I was writing, or they required a particular format--essay, drawing pictures, taking a walk in nature, etc. Well, the search is over. I simply googled 'writing prompts that don't suck' and found this wonderful site: http://awesomewritingprompts.tumblr.com/
The title is of the blog is "Writing Prompts That Don't Suck." Fancy that. Usually google gives me thousands of entries to sort through; however, I stop looking after the first three pages. Doesn't everyone? Anyway, I highly recommend this particular blog for any writer, of any genre. It's fun, current, usable, and, most importantly, it doesn't suck.