Well, I've an interest in pre-modern military technology (particularly fortification, thanks to that wascally Sidney Toy). But, how would I go about learning about the actual gear and equipment used by people? The basics are simple enough, but there's a lot of conflicting information out there.

Try Osprey's kine of books on fortifications.

http://www.ospreypublishing.com/list_by_series.php/ser=FOR

I am enjoying them myself.