Cap Guns (with values) is sort of a coffee table book, with three to five large color photos to a page. In all, it features somewhere between two and three hundred guns. That may sound like a lot, until you examine Backyard Buckaroo's Collecting Western Toy Guns. The photos are mostly black and white (with a 24-page color section), but feature more than 1300 guns, plus another thousand or so accessories like holsters, boxes, belt buckles, caps, and knives & tomahawks. Both books list suggested ranges of values, now out of date, but useful in determinating relative rarity.
Another difference is that about half of Cap Guns is devoted to cast iron pistols made between 1880 and 1940. This conveys the impression that half the guns in existence were cast iron. Western Toy Guns presents a much truer picture. Cast iron pistols are mixed in with the later diecast (aka pot metal) guns and shown to be an extreme minority. The cowboy shows dominating televison in the '50s and early '60s brought a tidal wave of cap guns to market. And that brings up Western Toy Guns one drawback - it features exclusively western stuff. Though the vast majority of pistols and rifles were western style, there were also military, detective, spy and space weapons, and a few of each make the cut in Cap Guns.
If all this puts you in the mood to see some guns, I invite you to start right here. Over the past year or so I've posted pics of more than fifty guns from my own collection, and there are a lot more on the way. You'll find those photos HERE. You should also pay a visit to nicholscapguns.com, the single greatest source of photos and info on the web.