If you're prepared to delve into them and chase hatches, do yourself a favor and buy Caddisflies, by Ames. There are hatch charts for specific regions of the Eastern US, tons of photos, patterns, and plenty of info about behavior etc of the different genus and species.
I'm slowly integrating closer matches for larvae, pupae, and adults in my boxes, but for the most part I just fish generic larvae, soft hackles, and cdc dries. Most activity/hatches I run into aren't condensed into a short time frame, so I think knowledge of the behavior, and a presentation that is congruent with it, is more important than tying on a perfect match.