What's the best Writer's Market book for nonfiction?

[The Backlash Cometh]

The one below says it's the best for fiction. So, I'm looking for its nonfiction equivalence:


http://www.writersdigestshop.com/product/novel-short-story-wrters-market-book/?r=prevbuy070610&et_mid=74613&rid=49854648

[sybylla]

1. You want one of these two

http://www.amazon.com/2011-Writers-Market-Robert-Brewer/dp/1582979480/ref=sr_1_1?ie=UTF8&qid=1295556713&sr=8-1

http://www.amazon.com/2011-Writers-Market-Deluxe-Online/dp/1582979499/ref=sr_1_2?ie=UTF8&qid=1295556713&sr=8-2


They are the full, general edition and include non-fiction markets in magazines and online as well. The only difference is that the one includes access to the online version which they promise to update throughout the year.

I hope this means you're ready to market the story you were working on a year or two ago when you sent me a couple of chapters. Good luck with it!