So where should one start, when considering how the bike should look? Well, browsing the Internet is definately the thing to do in my personal oppinion.
Google will get you far. Always remember, that Google is your friend! So by typing for example cafe racer, and selecting "Pictures", you will be able to find a lot of cool cafe racers to be inspired by. The ones I am most inspired by are shown below.
This bike is particularly cool... I love the spoked wheels, and the low look of the bike itself. The exhaust system is also very good looking, with the weldings still visible, to add to that raw look that the bike represents.
Another cool bike to be inspired by, is the Monkee #11 from the Danish custom bike creators, wrenchmonkees. See the link, in my links-box on the right.
I believe that this bike is one of the coolest looking custom cafe racers, that I have ever come across. The fact that it is stripped of all unnecessary components, adds to the cafe racer look and philosophy.
Some other sources of inspiration appear below.
So there You go... Some inspiration for a nice looking cafe racer!