Amazon.com, perhaps the largest internet retailer, they have a well known system of allowing their users to "review" products.
All the international Amazon websites allow customers to review products. Review a DRM product NOW as a way to warn others of the problems they may face because of DRM.
Once you have reviewed a product, post a link to your review as a comment below to encourage other DefectiveByDesign crew members to rate your review. If you see a product review that points out the DRM problems you can also rate that review highly so that others will see it.