Ditto on room and board - you can customize a few of the coffee tables and they have glass and white glass tops (the glass looks greenish in my opinion). You can look at all of the options in the store.

IKEA

http://www.roomandboard.com/m/catalog/living/cocktail-tables/portica-cocktail-tables


The above I've seen sold used in craigslist too.

Room and board lets you customize size, materials for top and legs separately, shape. Loooove them. Wait. They do that for tables but not sure about coffee tables.

How about this?
http://www.roomandboard.com/m/catalog/living/cocktail-tables/dunn-cocktail-table-with-glass-top

Not sure about the price point but you can try Mitchell Gold or Jonathan Adler. Maybe CB2.

I'm looking for a contemporary looking coffee table in either glass or white top finish, preferably square. There are a lot of the same thing online, but I'd really prefer to see it in person. Can you recommend any stores nearby that I should look in? I'd like to keep it under $1000. (Actually, I'd like to keep it under $500, but I know that a nice table won't be cheap.)

TIA