I know of one using SBRT in San Diego, but they haven't started recruiting yet. You can call them anyway:
Prospective Evaluation of SBRT for Metastatic Prostate CancerUT Southwestern (Dallas) is running a registry:
Clinical Registry for Oligometastic Disease, Consolidation Therapy, Debulking Prior to Chemotherapy, or Re-IrradiationYou don't have to have this done in a clinical trial. All you need is an RO willing to do it. I'd guess that you could get it done at UC Denver based on their recent study:
Is prostate-specific radiation still of any value in men diagnosed with distant metastases? Redux- Allen