Quick Thoughts: Much easier to use than some of the other sites. Apparently more limited range of choices on many of the models --> not as confusing. Decisions made can be clearly seen on image of the car.
http://www.toyota.com/prius/index.html
Options come as premade "packages" ( http://www.toyota.com/vehicles/2005/prius/options.html ). Colors come in predetermined exterior/ interior combinations (http://www.toyota.com/vehicles/2005/prius/color.html). Chris W. has put up some pictures of the Toyota Prius interior.