If you're using OS X Mountain Lion iTunes is available for syncing. Learn about that and other OS X Mountain Lion entertainment features here.
Just like your purchased music, all of your purchased TV shows and movies will be added to your iTunes library automatically. For other videos, your options are much more limited. iTunes doesn't allow you to rip DVDs or Blu-rays, so you won't be able to import movies or TV shows from your home collection. It's not compatible with all video formats either; you can only import video files that end in .mov, .m4v, or .mp4.
When you add a video file to iTunes, it'll appear under Movies (even if it's a TV show). However, your purchased TV shows will always appear in the TV Shows library.