Wine Barrels as Functional Pieces

I am so going to do this for one or two of my fall weddings this year! I have a couple of particular venues in mind that would lend itself so well to this look! So, now where does one go about getting these barrels? Does anyone know and if so, please share!
www.weddingsbylilly.com
www.weddingbee.com  
http://www.stylemepretty.com