1. A computer program product, comprising a computer usable medium having a computer readable program code embodied therein, said computer readable program code adapted to be executed to implement a method for automatic return letter generation, the method comprising: determining whether a source document with contact information includes one or more fields requiring data; responsive to the determining, automatically generating a response document based on the required data; automatically generating a document identifier based on the contact information and the response document; transmitting the response document based on the contact information to a recipient; responsive to receiving response data from the recipient, matching the response data with the source document using the document identifier; electronically merging the response data with the source document to yield a merged document; and processing the merged document.