I have every Calvin and Hobbes ever. Nowadays there is a really cool collection with all of them in a box set, but I just have all of the books that ever came out, all 20 something of them.
The real last comic is at the end of the book "Lets Go Exploring".
Its funny if you read them as a kid because you can go back and re-read them and get so many more jokes than you did when you were little.