1. I heartily recommend The Reader's Guide to Recycled Literature, in Salem, Oregon. This used bookstore was the best, out of all the ones I visited on my spring break vacation. I might go so far, as to say it's better than the famous Powell's bookstore in Portland. Why? I tried to sell some of my Nancy Drew Files books to Powell's, but I was rejected because I had too many books, and because that series was "not popular enough".
Like most book places, Powell's doesn't make much effort to stock anything, besides the original, yellow-back Nancy Drew series. If you're looking for one of the hundreds of Nancy Drew books written after 1981, your odds of finding it are a matter of luck.
Salem's store had a good supply of Nancy Drew books, from all the various Nancy Drew series. They even had a complete set of "Nancy Drew on Campus", the spinoff series where she goes to college! I had to prevent myself from buying all of them, on the spot. So, yes, I definitely recommend this store!
2. I also would recommend Brewster Rockit, a consistently funny comic strip that does a great job of being topical, even though it's not set in the modern day. He has two books available on the iTunes store, although they're made up of the older strips.
3. Finally, I really like Ernie Bushmiller's Nancy comic strip. It's very simple, and also very solid. I love the art style, and my family members also enjoy it. I don't like the modern version of the strip, which is mostly about country music and Nancy's attractive aunt going on nostalgia trips.
The same company behind The Complete Peanuts is making an effort to publish all the Nancy strips. So far, they've published three books, which contain all the strips from 1943 to 1951. Sundays aren't included. The full strip ran from 1925 to 1982, so they've got a lot of work left to do! They seem to be releasing new books, at the rate of one every other year.