I highly suspect it's from Peachpit.com book orders. I have a couple of those charges that escaped me from the past as well, and coincidentally ordered a physical and an eBook from this site for just about the amount on my statement.
Also appears on statements as "AWL*PEARSON EDUCATION - 800-232-6556, NJ"
What is it?
Yes, it is Peachpit.com. I just ordered an ebook and this charge appeared under the AWL Pearson moniker.
I bought a book <<Into. to the Analysis of Algorithm>> from Addison-Wesley website. It escaped me as well when I looked at my credit statement. Later I noticed the publisher(what the AWL stands for) belongs to Pearson from the book's cover page.