LeAnn Rimes is planning to tie the knot with Eddie Cibrian on a private ranch in Montana. Sources tell us the singer “has approached a number of owners of private ranches about a May or June wedding.” Rimes, 28, met Cibrian, 37, on the set of TV movie “Northern Lights” when they were both married to other people. They took a romantic break in Montana last August. She wrote on Twitter at the time, “Going to lock myself up in my cabin with Eddie Cibrian, if you know what I mean,” adding, “Montana is the most peaceful and beautiful place I could be [with Eddie] right now. We have NO service other than the main lodge where we are staying, so we are escaping . . . Montana is magical! Peace it brings!” Rimes and Cibrian got engaged at Christmas and confirmed they “are very happy,” but she recently claimed she was in no rush to wed. Her rep last night said, “No comment.” A rep for Cibrian didn’t get back to us.