I did a wiki-search on polearms recently as a result of an argument with a fellow DM over this very issue.
It was actually surprising to see how many identified types of polearms were not covered by DnD.
The Roundhead was my particular favorite
Are there any existing feats or powers out there that handle setting against charges?
Remember to take everything you read about medieval weapons and armor with a 5 pound bag of salt. A LARGE amount of it is the result of crummy 19th century amateur scholarship (very similar to a lot of what you find online these days, lol).
Most of the names of the various pole arms for instance were never contemporary, they were terms invented in the 19th century. Over time things have gotten even more confabulated by people mistaking a lot of this pseudo knowledge for established fact (hey it was in a book, its a fact).

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.