Here are the locations of all books:

01 - 20,000 Leagues Under the Sea - Shrine of Zenithar near Swindler's Den
02 - A Tale of Two cities - Shrine of Dibella outside Old Hroldan Inn
03 - Alice's Adventures in Wonderland - Shrine of Talos west of the College of Winterhold
04 - Catcher in the Rye - Mara's Eye pond, atop a crate on a boat
05 - Charlotte's Web - Outside Cold Rock Pass
06 - David Copperfield - Riften Docks, on top of a barrel near a big ship
07 - Don Quixote - Solitude docks, in Vittoria's little stone building
08 - Dr. Jekyll and Mr. Hyde - Widow's Watch ruins, on the second floor
09 - Frankenstein - Dushnikh Yal, on a shelf by the alchemy area
10 - Gulliver's Travels - Next to a knapsack by a tree trunk on the road to Falkreath
11 - Hamlet - Small bandit camp west of the Helgen escape exit
12 - Journey to the Center of the Earth - On top of a barrel in Nilheim camp
13 - Little Women - Outside Honeystrand Grove
14 - Lord of the Flies - On the way to High Hrothgar, where Karita is 
15 - Moby Dick - Next to a dead hunter in Autumnshade Clearing
16 - Romeo and Juliet - Dead Lovers Camp (unmarked location), on the road that travels north from Old Hroldan
17 - The Great Gatsby - Witchmist Grove, on top of a barrel by the bed
18 - The Lord of the Rings, Vol I - Cabin of the Orphan's Tear
19 - The Red Badge of Courage - Angi's Camp, by the cooking spit
20 - The Scarlet Letter - By the skeleton in Wayward Pass
21 - The Time Machine - Outside Kolskeggr Mine
22 - The Wind in the Willows - South Skybound Watch tower, by the topmost chest
23 - To Kill a Mockingbird - Inside Four Skull Lookout
24 - War and Peace - Next to a Pine Thrush nest atop Cradle Stone Tower
25 - Tom Sawyer - By a chicken nest next to Winterhold Jarl's Longhouse 
26 - Huckleberry Finn - Wreck of the Winter War, atop a crate by the cooking spit

If, for whatever reason, you still cannot find them, or want to access all at once, open the console and type 'coc aaaBlueBooks' without quotes. This will take you to the testing cell I used to check the books and take pictures. Pick up the books you want, then open the console again, and type 'coc riverwood' without quotes. Enjoy!