Best Reference Books for Writers?

Ooh, ooh--library sale! I just went to two of them, searching for writing reference books. Obviously, some of it will depend on what you're writing, but this is what I looked for:

Compass American Guides: These are not like the Fodor's books that just list places to go in a state or a city. They are full color and have some nice narrative about the locations and history. I should note though that you can probably get tourist books and maps for free from the state government tourism sites, and also for some of the big tourist cities like New Orleans.

Antiques: Anything on antique hunting. I was specifically looking for more general information for the layman, rather than collectors. But I did see a lot of books on specific types of antiques like glassware.

Auction Catologs: This was a big score for me. I have an auction in my book and had been putting off buying a catalog from an auction house. I would have needed an artwork one, and those cost $65. When I checked the antique section, I found about five of them from past auctions, all for no more than $2 and they were for artwork. Not only that, one of them had writing in it from the auction, and another had an After Sales report stuck inside that including a painting that sold for over $1 million. One library sale also had stamp auctions, and the other hand coin auctions--the coin auctions were in Germany!

Depends on what kind of stories you write. Recently I've bought a dozen books about the Puritans in 17th c. New England, in preparation for my next WIP. I'd love a copy of The History of Salem, Massachusetts by Sidney Perley if your library has one for sale.

Library sales are good places to get out of print books like this. If you're looking for up to date information, not so good. Medicine and science references, probably not going to find new ones at a sale, but if you're writing a historical novel, you might like some older texts contemporary with your story.

I go to the Internet for cutting edge info, myself. Tech references date so fast.

I love library sales! I spend hours at them, and only end up spending about $6 for two or three bags of books.

As for what to look for--I just go over every book until I see something that might help my writing. Hard to say. Sorry I'm not much help!

I don't know what reference books would be the most helpful to you (other than the classics like Elements of Style), but here's a couple of other suggestions. It used to be that library book sale buyers were mostly locals just buying a book or two, but now a lot of Amazon Marketplace/eBay used book dealers come to buy. Get there early; bring a big study bag; if you see a good, clean copy of a book that you might be interested in, put it in your bag and decide later if you really want it or not. Don't worry too much about best-sellers from two years ago; you can always get those cheap, or for free if you have a bunch of book-loving friends.

My suggestions are books on marketing and books on ruling the world over the internet. Both are likely to help a writer.