I've emailed a few authors over the years. Most only once, one fellow twice. You have to be a little patient, these folks have other things to do than clear their email backlog every few hours, but I almost always get a reply within a week, and the replies have always been positive.

Only once did I fail to get a gracious reply, and I feel that was my fault. A favorite author has about 50 short stories spread across half a dozen print collections, all but one decades out of print. I suggested he put together some master collection in ebook form to make it easier for fans to collect all of the stories. He didn't reply.

I feel I should have known better, because on his website he kind of vaguely but firmly mentions he is not interested in revisiting old work and updating it. I was disappointed, but not surprised when he ignored the suggestion and sent no reply.