By this I mean, are there any books that look at the role of cavalry in warfare and how they were used in scouting, how charges were made and what their tactical role was? I know that there are a few books out there which deal with horses, their equipment and their social role/value, but I don't know of any that detail their actual use in warfare.
For Norman and Anglo-Norman cavalry warfare, I would look at R. Allen Brown's "The Status of the Norman Knight" and "The Battle of Hastings", both located within Strickland's Anglo-Norman Warfare: Studies in Late Anglo-Saxon and Anglo-Norman Military Organization. Hell, I would just look through the entire book (it's a collection of related essays and papers, not a monograph) if you can at all easily find a copy. I'm not aware of any really good books that cover medieval cavalry warfare writ large; such books tend to result in generalizations by non-experts.