In my case, there was never a lot it, and what there was of major artists, I already have representative samples of almost all of them. For example, I really don’t need an Aparo cover; I have 3 panel pages, and a fanzine cover. But, why I can’t find images of PS from Impulse? Captain Adam (missed one, once)? When they have slipped through, it’s usually because I already spent my spare cash on something else, or really don’t care for the image. And then I live to regret it for years.
And by the way, I do buy outside my area on occasion. I commissioned Keith Williams for a Martian Manhunter piece I am waiting for, and I am just barely resisting the urge to buy some Jordi Bernet art. He is really terrific.