The style books I recall say that both are correct, and don’t give a preference. I, too, prefer to place a comma before the “and”.
I can’t recall what Strunk and White or the Chicago Manual say. Based on my past experience, they’ll say that it’s better NOT to use the last comma, if only to make me look bad.
Let me chime in here wearing my freelance-copyeditor hat. The serial-comma question is the one I’m most frequently asked when I tell people what I do. The answers here are all correct – it’s a matter of choice and most of the time either is correct – but missbunny makes an important point: the serial comma removes any chance of ambiguity. A popular illustration of this is the alleged book dedication “To my parents, Ayn Rand and God.” Use of the serial comma here would have made it clear that the writer is not a half-deity.
And FWIW, the only style guide I know of that specifically omits the serial comma is AP (Associated Press), and that’s only because it’s newspaper style, which prefers conciseness. (Yeah, like a comma takes up so much space.) Chicago prescribes the serial comma.
It’s very much a style question, so, if you’re writing for publication, you’ll want to know the preference of your editor or the house style. If it’s just for yourself, it’s up to your personal preference.
I tend to omit the serial comma myself, on the grounds that a comma, in a list, is acting as an abbreviation for the word “and.” At the end of the list, there already is an “and,” thus a comma is superfluous.
Blasphemy! The final comma is necessary because a comma denotes a slight pause in speech, and when speaking the items of a list, you most certainly make a slight pause before the “and.”
Bonus question: Tell a story in which you use the word “and” five times in a row and it makes sense.
Pointing to a sign over a tavern that read “Bear and Fox Tavern”, James said to Sam, “That sign is hard to read. There should be more space between “Bear” and “and”, and “and” and Fox.”