Haha. Wilson has two seperate departments in two locations to deal with defective rackets. Is that impressive customer service or does it simply mean they always get a lot of returns...You might have to have the retailer send it in for you. I'm not sure about Dunlop.
I can tell you a story that might give you a little insight into the process. I had a friend that broke a Wilson racquet while playing with me. He had the retailer send it back. It seems that Wilson has a "investagative lab" that determines if a frame was cracked because of defect or abuse. They returned his frame saying it was cracked from abuse.
There is an appeal process, believe it or not. You send the frame, yourself, to another Wilson location for further examination. This time he included a note I wrote saying that I was with him when it broke and that I witnessed no abuse. He noticed the crack after hitting a big overhead.
They then changed their decision and sent him a new, upgraded frame. The exact frame he broke had been discountinued.