Denise and Alan Fields' planner - Bridal Bargains Wedding Planner: The Dollars and Sense Guide to Planning Your Wedding - is a complement to their book of the same name, which I thought was GREAT!
It tells you about all the wedding dress ripoffs and scams to avoid, gives you an idea of how much the average wedding costs, and offers lots of realistic ways to save money (well, OK, except the part about decorating with balloons. That was just...cheesey...).
Even Disney Brides can use it to cut costs on the gown, outside floral, invitations, etc.