Adding a free download file to a paid product

[andyp]

I am building a site for a Printing Company. When a customer has bought a service (i.e. ordered 5000 leaflets) they then need to be able to access/download some PDF files of artwork guidelines. Is this possible? The Custom Fields seems to only allow download files at the Add to Cart phase and it needs to be once payment has been made. Can I add a link to the order email/invoice? Or is there a better way? Thanks in advance!