I've recently started getting a rash of junk mail to a particular email address. I give out unique addresses to all organizations I deal with, so I know exactly who has this address on file. The emails are not of a marketing nature (mostly phishing/work-from-home scams), so to me it appears that someone may have compromised at least a list of this organization's customer email addresses.
My attempts to inform the organization (an online retailer) that there may be a problem via all the channels I've been able to find have so far not elicited a response. I'm continuing to try, but if ultimately I can't get anyone at the organization to even acknowledge that I'm contacting them, what would be the next step to make sure someone is looking (or has looked) at this?