He was referring to not getting an email about the sale of the list, not him not receiving something he paid for.
This is terribly embarrassing, I just got your PM telling me the PayPal email address you paid with, and I cross referenced it with the payments I may or may not have received from it.
It turns out that you did in fact send me a payment, but the software running the backed of my site never registered you as a paid user...and you paid quite some time ago (for Aprils list, and there has been another list since then).
As my way of apologizing, I've given you access to the list you paid for (Aprils list release), May's trackback list & you'll get the next list I put out at no cost.