Teresa-
Since most of us that post here are not in Europe, I would recommend contacting your local physcian and asking about some clinics that offer this type of surgery. One thing I'd like to point out is there is no such thing as "simple" brain surgery, and as I'm sure you're aware, there are many risks involved with brain surgery such as irreversible brain damage. I would rather live with OCD than put myself at high risk for something going wrong during the surgery and spending the rest of my life with a debilitating physical problem. Doctors still don't fully understand how OCD works, so asking a physcian to perform surgery on you to fix the OCD when even neurosurgeons don't understand how it works is very risky.
There have been a few cases from a book I read where people have had surgery on their brains for extreme cases of OCD, but these instances are few and far between. Some of the criteria to be eligible for brain surgery for OCD include non-responsiveness to all medications and all types of therapy, but in most cases, this does not happen.
Please talk to your physcian before considering such a serious surgery.