There are some white granites that have been very popular because they let people get the Carrara/Calacatta look in their kitchens without worrying about maintenance as much. Some granites AKDO carries that look more similar to white marbles are:

White Fantasy ( http://akdo.com/products_detail_slabs.asp?pname=White+Fantasy+&catid=81&mcatid=12)
White Pearl ( http://akdo.com/products_detail_slabs.asp?pname=White+Pearl&catid=81&mcatid=12)
Andromeda White ( http://akdo.com/products_detail_slabs.asp?pname=Andromeda+White&catid=81&mcatid=12)

It is hard to talk about cost because there are a lot of factors like the color marble you want, the granite you select, the thickness of the stone and the edge you select. Best to check with your fabricator on that.