| The basic steps for adding|
videos to the library:
To use your video files with "metadata" like summaries, cast info, DVD covers, thumbnails, and more, you need to add those video files to the video library by following these steps: -->
There are a couple of important parts to getting things imported into your XBMC library. First, the metadata for the video file should exist someplace (the metadata are things like the title of the show, the plot description, the season and episode number if the video file happens to be an episode of a TV series, the actors, the director, cover art and episode art, etc.) The second part is naming the video files so the file gets matched up with the metadata available online.
XBMC uses plugins called scrapers to pull information from a video file and coordinate it with a source of metadata available someplace on the internet. For a TV show the scraper basically looks for the show name, season number, and episode number. The default scrapers look at TheTVDB.com (for TV shows) and TheMovieDB.org (for Movies).
If some video file is not scraping properly, the first step is to go to the website of the scraper you are using on that source and see if the video is already listed there. If you can't find an entry on one of those two sites for the video you're interested in, you can hunt for different scrapers which search other websites for metadata (and go through the same process of making sure your show is listed there, then naming the video files to match). Alternatively, you can create new entries on those sites with some basic information about your show, and then let the scrapers do their work. This is nice, because it means that other people will benefit from your work, and may contribute additional information about the show over time. Adding info to a site like TheTVDB.org is easy, but make sure you read the site rules before you start adding.
If none of that works, you can create .nfo files for each video by hand so that XBMC will bypass the normal looking online for information about your show. This is the least attractive option, though. It's a lot of work, and it doesn't benefit anyone else the way creating entries on the metadata sites does.
The menu on the right hand side will walk you through all of these steps.