1. A method for selecting at least one product for association with a document for display in a user interface rendered by a computing device comprising: analyzing at least a portion of the document for at least frequency of words in the document; constructing a keyword query search string at least partially based on words of the document having highest frequencies; searching product records in a products database to identify products satisfying the constructed keyword query search string; selecting at least one product from the identified products for display in the user interface.