Update: Thanks to Amanda for the proper source of the image! It can be found at You Can't Be Serious and you can request to have a postcard mailed to you... Isn't that awesome?!
Which leads me to an interesting situation... I posted the image after doing about ten minutes of research online. I first spotted the image via Pinterest and then tracked it to a Tumblr site and then to a website. The link to the website was not a specific URL (meaning it took me to the home page). I tried to do a couple of local searches for "quotations", etc. but could not find it. I suppose I should have just given up there, but I felt like the chances were good that it originated from that site.
ANYWAY, I guess what it boils down to is that I need to rant for just a second about people not pinning or crediting from the proper source! Don't pin (or post) an image that doesn't credit a proper source. When you pin from a blog, pin from the actual post NOT from the home page or a search page. I always try to give credit to the artist because I understand - my "Be Awesome" print has been pinned thousands of times on Pinterest and who knows how many on Tumblr. Hopefully this all makes sense... And, I'm going to do a better job of following my own advice! If you have anything to add to the topic I would love to hear your thoughts!