Does domain name affect placement on search engines? for example, if I had a pizza delivery biz in Chicago and it's called www.chicagopizza.com would that give better SE results than www.joespizza.com?

I don't think so.

You might want to get this moved to the SEO forum.

simple answer is No

it could be called 73southstreet for example and that wouldn't affect anything either.

i don't think it would matter. i have a site that has a general name but gets good results. everyone tells me it does not work but i played with the meta tag. i have 2 sites that look the same but have different meta tags and there is a noticeable difference in the placement they get.

expedia, amazon, lonelyplanet, wired, fark... the name is irrelevant. Good content brings all these sites traffic because everyone links to them...(well, almost everyone)