I also got one..
I tried yesterday to get someone on the phone but kept getting a busy signal( now I know why!). This kind of thing drives me nuts! Anyway, during my 25 minutes of listening to pre-recorded messages, I did hear them mention that you could go directly to their website and print out a return label. I haven't tried it yet, so I am not sure if it will be a prepaid one or not, but I too am NOT paying for return postage for this.
Here is the contact info for anyone who may need to get in touch with them:

phone# 1-800-820-6077
website: www.rodalequickpay.com