Are there any examples of ancient comedians? Or famous story tellers who focused more on humor than anything else? Do we know any ancient jokes aside from the graffiti found in Roman ruins?
I'm not sure this is the exact angle you're looking for (eg, a stand-up comedian who specialized in set-up, punchline jokes), but Greek comedy can be pretty humorous. A lot of people point to the playwright Aristophanes. For example, his Lysistrata (c. 411 BC) is a satirical play where the women abstain from having sex with their husbands so that they would try to negotiate peace with the Spartans.
For example, the opening scene contains a bit of what can be construed as phallic humor:
CALONICE What kind of an object is it?
LYSISTRATA A tremendous thing!
CALONICE And long?
LYSISTRATA Indeed, it may be very lengthy.
A lot of his plays can be found on Project Gutenberg.
The big names in ancient comedy are Aristophanes, who wrote "Old Comedy" (political, satyrical, rude and over-the-top), and Menander who wrote "New Comedy" (Moral, realistic, even Sit-com-ish). For Romans, Plautus and Terrence, who was a little more sober (and boring) than Plautus, inherit the tradition of New Comedy. A lot of their material is translation from Menander's Greek.
The oldest example of a 'Joke Book' is the Greek Philogelos from the 4th Century AD. I don't know anything about it to tell you the truth.
Anyway, Aristophanes' plays are absolute treasures. Read them if you get the chance.
In Roman culture, Humor was often focused in some short poems and comedy plays for the most part. Ovid had a kind of satirical sense of humor in his poems for example.
Plautus wrote some hilarious plays. His style of comedy was a bit on the goofy, lowbrow side. There was slapstick, mistaken identity, and of course penis jokes. In fact, his plays inspired Sondheim's musical "A Funny Thing Happened on the Way to the Forum" (1966), which kind of synthesized the plot elements and stock characters from a number of Plautus plays to form a new story which was overall very faithful to the style of ancient comedy.
Here's a good one liner from Plautus' comedy Pseudolus:
Ballio At night, when the Captain was going on guard, and when you were >going with him, did the sword of the officer fit your scabbard?
(a very crude play on words)
You can find a lot of his plays in translation on perseus
hi! you'll find some examples of jokes in the FAQ (link on sidebar)