Where can I find instructional videos on medieval sword fighting?

There is only so much you can learn from videos, and there are a lot of videos out there that aren't particularly good. My first and best advice is to find a western martial arts group near you. It's still a fairly small community, but expanding fast.

Here are some lists of groups and schools. Maybe there is one in your area:

http://hroarr.com/organisations-and-clubs.html

http://hemaalliance.com/?page_id=331

Look for videos by the groups listed in the sites above. That will give you some assurance that they know what they are talking about. It's not a guarantee, but it's better than a bunch of yahoos fooling around in their back yards.

try this video, it will help you improve your sword fighting abilities, the videos are in a series too.

http://www.youtube.com/watch?v=l5rgnk6Smfw&feature...

so good luck.

http://www.youtube.com/ You can find anything on there.