Score one for the little guys. As reported in this section two months ago, stores selling used CDs came under fire this summer from four major record corportions (CEMA, Uni, Sony, and WEA), not to mention Garth Brooks. The companies, claiming that sales of secondhand discs deprived artists of royalties, announced they would not underwrite ads for those retailers. In turn, the stores (most notably the California-based Wherehouse chain) brought lawsuits against the record companies for restraint of trade. With ugly court battles brewing and Brooks’ image tarnished, the distributors blinked. By Labor Day, all four companies had capitulated, on the condition that stores don’t use the company-funded ads to plug the sale of used CDs. Brooks, meanwhile, continues his anti-used-disc rants, most recently on the Aug. 30 Tonight Show.