In a word NO, its actually quite tricky getting all the exact sizes etc to match up, and like all things customisable you'll end up blowing ya budget before you finish, (been there done that). Get a complete bike with the best frame possible and then upgrade from there. An older bike with last years colours/gears on sale for example is generally the best way of doing this.

On the other hand the sense of ownership and individuality that comes with building a bike up from scratch is great.