You don't have to be a huge web design shop to successfully build fluid websites. A good place to start building sites like this is the 1140 grid[0]. We've knocked out a couple of client sites with it [1]. Getting the basic layout to resize is super easy...it's the positioning details for the media queries that can take hours.

[0]: http://cssgrid.net/

[1]: http://etbeancounter.com/