Perhaps you need to become more organized and one of the things you need is a laptop/notebook bag. Many people find that having a bag specifically for their notebook/laptop aids in organizing everything else you carry.

About.com has a very good article "Laptop Bag Buyer's Guide" which discusses the types of considerations you make in selecting a laptop bag. It even discusses laptop bag styles, along with all the other considerations.

You may also wish to take a peek at productdose.com's article "Top Ten Coolest Laptop Cases". The top bag in this lineup is the Crumpler Cashmere Blazer Laptop Case (also pictured here beside this article).