You want to use the GDR 2. (Sometimes called Data Dude)
This allows for a completely offline solution. You don't need to have SQL Server installed on your machine for this to work. (In fact the GDR is the first version that does not care if you have SQL Server installed.)
I use the GDR for my db (a team of 3 devs and 2 testers) and it works GREAT!
Here is a link for the GDR 2 release:
http://blogs.msdn.com/vstsdb/archive/2009/04/21/microsoft-visual-studio-team-system-2008-database-edition-gdr-r2.aspx
And this is a link to the actual bits:
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=bb3ad767-5f69-4db9-b1c9-8f55759846ed
The basic use is to import from an existing DB and server. (You will probably want a server project and 1 or more DB Projects)
You can then make your changes off line. When you are ready to send you changes back to the DB you can delploy (make sure you set up your deploy options first as I think the default is to drop the db and re-deploy). You can also do a Data->Schema Compare in Visual Studio and comapre your project to your database then get a script of changes from the diff output.
It takes a bit of work, but it really allows great source control and is easy once you get the hang of it. (I have my db auto deploy in my night time build twice a week.)