Please check out Stage 1 for the information needed to locate the cache inside the Lisle Library. I would not call Conan slow, but you may want to tread lightly if you do so while getting the information needed for Stage 2 (The sun is relenteless so the Hint below now contains Stage 2 information).
There are some very fine books on astronomy and other topics inside, but I wouldn't ask Conan if I were you. First of all, you are looking for a geocaching book. More importantly, Conan really expects you to know the Dewey Decimal System and he is not a very patient or understanding librarian. Or perhaps you think you can find the book hosting the cache on your own or you want to tempt fate and ask Conan...
(845) UHF Conan The Librarian - YouTube
Cache hidden with permission of the Lisle Library District. A special thank you to the LLD for being willing to host this cache. The recent renovation makes the Library an even better resource for the community. After you find the cache, check out the rest of the library. And Downtown Lisle is right down the street as well.
Accessible
Monday to Friday 9:30 AM to 9:00 PM
Saturday 9:30 AM to 5:00 PM
Sunday 1:00 PM to 5:00 PM