Here are a couple of links I found that seem to be what you are looking for. They appear to be cached by Google, but I couldn't find them on the Marketo web site.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CEIQFjAA&url=http%3A%2F%2Fblog.marketo.com%2Fblog%2F2009%2F08%2Flead-nurturing-roi-and-content-mapping.html&ei=sQ_2UO0gqrzRAe3-gLAO&usg=AFQjCNFdVeeFzlVg_OPpcA78WeWA9wXJjA&sig2=hh8j6beEaaasjxNG5qh1lw
http://webcache.googleusercontent.com/search?q=cache:Bb3EKps75c8J:docs.cdn.marketo.com/Sample-Resource-Spreadsheet.xlsx+&cd=2&hl=en&ct=clnk&gl=us