Quote from Sherry_205423 on Nov 8^th, 2012, 12:17pm:

 
HI Sherry,
 
I have several vintage pieces on the site, so no problem there; however I have taken the images from Public Domain Vintage sites and therefore have always been able to offer a link to 'certify' the PD status.  
 
Tom Rent at Comical Captions buys old vintage photos from swap meets and he is allowed to use those too, so I'm guessing you'll be fine.  Just make sure you put a note in the Reviewers Notes section when you create the cards to the effect of the 'year' and any other info on where you go the photo.

Here are some links to help you out as you are just getting started:
 
GCU Intellectual Property List (also known as the Taboo List)
http://www.gcuwiki.com/ip.html
 
Image Guidelines
http://www.gcuwiki.com/ig.html
Copied and Pasted from above URL:  
Vintage Postcards & Findings - Parts of Vintage work, such as from vintage postcards can not be used in their entirety, but parts can be used as elements in your own original piece of art.
Specific note to Artists - Vintage works, particularly works pre 1978 copyright laws, have limited, non-existent or expired copyright protection particularly when used in a new, creative or ``reworked`` manner. It is your responsibility as the artist to ensure that your images use vintage findings as elements in a new composition thus creating your own original piece of art. Using the original work ``as is`` to create a card is merely ``copying`` and is not permitted on GCU. Reviewers may ask you to confirm that the work is an original composition of vintage elements.
 
Hope this helps.