I love 'em, as safe places to leave books when the weather's bad or if the particular area doesn't seem friendly to books-in-the-open. Some of them are really beautiful, too, and/or whimsical.
A fairly recent Chit-Chat thread about LFLs ( http://www.bookcrossing.com/---/535838
) may be of interest; it includes a link to a photo of one of my favorite local LFLs, handsomely decorated to match the building it sits next to - a funeral parlor!
Another favorite is this faerie-tree-themed one in Hampton NH (the photo's in the release notes):http://www.bookcrossing.com/---/13414362/
Not the most weatherproof style, but it's utterly charming! (Note that the roof is decorated as an open book.)
As with other book-swap-shelf releases, I don't get as many catches from the LFL releases as from books left in more public - and unexpected - places, but I have had some very nice LFL catches, including:http://www.bookcrossing.com/---/13642115http://www.bookcrossing.com/---/14327627/http://www.bookcrossing.com/---/535282
On the other hand, there have been times when I've re-visited LFLs only to find books I'd left there months or even years before, still sitting there. No way to know if they'd been taken, read, and returned, or if nobody has chosen them yet. I usually just leave them, but once in a while I'll relocate one to some other spot, just to shake things up a bit.
I don't have an LFL of my own, though I'd love to start one. Maybe I'll ask the local park service if they'd like to have one, if I offer to help keep it tidy and well-stocked...
As for finding LFLs nearby, I do use the Little Free Library Map ( https://littlefreelibrary.org/ourmap/
); sometimes I choose the city/state option and select specific towns, but I've also tried the "near me" option to find LFLs within a range of distances, from 1 mile to 20. [The 1-mile option sounds good if you're hoping to find one within walking distance; the 20-mile one might give you some ideas for a road trip!]