German media giant Bertelsmann said Tuesday it’s buying Gotham-based music club Columbia House in a deal said to be worth about $400 million.Columbia is 85% owned by New York buyout firm the Blackstone Group. Sony and Time Warner each hold a 7.5% stake. Columbia House has 8 million members in the U.S., Mexico and Canada and sells music online and through the mail. Bertelsmann’s BMG Direct operates its own mail order retail biz, sending out 68 million catalogs annually. “This move gives us strategic access to the growing business with DVDs, as well as broadening our customer base in the U.S. market,” said Ewald Walgenbach, CEO of Bertelsmann’s DirectGroup unit.