Read Google uses Gmail to track a history of things you buy — and it's hard to delete by Todd Haselton,Megan Graham (CNBC)

Google collects the purchases you've made, including from other stores and sites such as Amazon, and saves them on a page called Purchases.

Apparently is a reasonable place one could start for creating acquisition posts on their website. The downside is the realization that Google is tracking all of this without making it more obvious.