creating metadata?

I have a question that hopefully someone here can help me out with. I’ve been using Sapphire for all my videos, and it’s awesome. I particularly like the fact that it pulls down art and metadata from IMDB for the movies I’ve ripped to my Apple TV. However, not all the movies I’ve sent are commercial releases. I have a LOT of home videos from reunions, sporting events, vacations, etc. and I’d like to be able to have “poster art” and descriptions for them show up in Sapphire. Also, is it possible to get these to show up in the “TV Shows” tab in Sapphire rather than under “Movies”?

Hope my convoluted question makes sense to someone. :?