Another suggestions is to ttake pictures of friends or family members from different angles, then practice using those!
I personally find working from photographs (especially ones I made) to be useful and inspiring when they show different angles on the same object. It gives you a better understanding of their structure and the diversity. Using different models is especially useful if you're stuck with similar looking faces.
You can pretty much stylize noses however you want once you understand their true anatomy.
Here are some sample tutorials for you that break noses down for you:
http://cataclysm-x.deviantart.com/art/Tutorial-how-to-draw-noses-44708765
http://conceptcookie.deviantart.com/art/Nose-Tutorial-Resource-342487080
http://browse.deviantart.com/art/Nose-Tutorial-120934771