Favorite Place to Buy Knitting Books? Used or New?

So I have come to discover that used knitting books can be in perfectly good to excellent condition, yet cost anywhere from $1 to $4 (fraction of their 'new' price). I currently live in Kansas City, Missouri and a few years ago discovered we have a second-hand chain charity store called "Savers". They are amazing! Many people donate knitting needles and knitting books (as well as perfectly good and unused yarn!) because either someone has passed away so they are donating it to Savers (proceeds go to charity). Or because the donator gave up on knitting. lol

I've also realized that Amazon sells many books second-hand (used) and often you can get cheap or free shipping on the books. This has made a HUGE difference in how much I am paying for my craft books such as knitting books.

My question to you guys - Where are YOUR favorite places (in person and/or website) that you like to buy knitting books?

Would you rather have a fresh, new book? If so, where do you do you go usually to check out the knitting books?

If you are also someone that buys used knitting books, where do you go to look for them? And have any tips on buying them?

One tip I do have on used books - Smell them first. Sometimes the person was a smoker and you won't realize it until you put your nose right up to it and sniff.

Thanks!
Cindy (aka on LibraryThing and Ravelry: AstroGirlBunny)