Where can you find all the poems Shel Silverstein ever wrote?
The best place to get them would be the books that he has published.
As listed on ShelSilverstein.com, his books are
- Falling Up
- A Giraffe and a Half
- The Giving Tree
- Lafcadio, the Lion Who Shot Back
- A Light in the Attic
- The Missing Piece
- The Missing Piece Meets the Big O
- Runny Babbit
- Where the Sidewalk Ends
- Who Wants a Cheap Rhinoceros?
There are others, including Uncle Shelby's ABZ Book, which is hilarious. But the ABZ Book, as well as his other work, is more appropriate for adults.
Some of his poetry is posted on these sites:
As with most other authors who have books in print, you can only find selections of his work online. To read it all, you will need to get access to the actual books, by buying them, or borrowing from a friend or a library. :)