One thing that many beginning photographers have issues with is posing their subjects. As far as that goes, even photographers who’ve been doing this for a while can get stumped on posing their subjects.
I found a great resource called PortraitTutor.com which has some helpful information on basic portrait information and some posing ideas. However, they sell a posing guide of over a thousand poses for all types of subjects. These poses are both traditional and contemporary.
This looks interesting enough to invest in. I think that many photographers get stuck and with a resource like this, coming up with new and unique looking images would really help them expand their abilities and skills.