i'm creating a custom object to handle print/promo item requests from salespeople. 

all of our one sheets reside in the documents tab.  I tried to create a custom lookup field that referenced a certain folder in the documents tab so the user could choose the document to be printed, but it seems that "documents" is not an available option when creating the lookup field.

does anyone know another way of accomplishing this?  basically i want the user to be able to choose a document from the documents tab in SF via lookup field.

thanks!