Amazon and Warner Bros. are close to resolving a dispute that has kept customers from being able to pre-order movies from the studio, according to a person with knowledge of the situation. Home-video customers can now pre-order the DVD and Blu-ray version of “Transcendence,” due out in disc format from the Time Warner studio on July 22, according to the Amazon website. Seattle-based Amazon wasn’t accepting preorders of Warner Bros. films as it sought price concessions. The person, who asked not to be identified because the dispute is private, didn’t provide specifics of the talks. Amazon, the world’s biggest online retailer, has been locked in disputes with media companies as it seeks to use its heft to impose better terms from its vendors.