Athame is a Wiccan term. The rest of us just call it a ritual dagger, "blade" or knife. I see swords as nothing more than a supersized version. Anything elongated, especially with a point, is used to direct energy. And I really do mean anything. The symbolism is the same as an arrow really.
I personally do not use them in magick, but I know that plenty of ceremonial magicians do.
Seeing that most people do not know how to blacksmith, I don't think you can make one yourself. The dull wooden or metal athame is, in my opinion, ridiculous. Just use a wand or staff if you don't want a sharp object.
Swords as ritual tools are generally used in a threatening way. Swords, unlike knives, have only one purpose -- to fight with. Knives on the other hand are far more versatile as a tool. But swords have a symbolic side to them that knives/daggers do not, and that's the same symbolism you find in tarot.