I hope you are a fan of Stephen Powers, aka ESPO. His mailing list is a wonderful glimpse into a graffiti artist turned fine artist that still manages to do large scale public works (enormous scale to be honest). Over on his webstore e recently added a selection of his sketch book drawings. They are pricey (understandably) but, fortunately, the Internet is free to browse. I suggest clicking through not only to see how his process comes to life but simply to remind yourself that doodling every day is an excellent practice if you can manage it.