Usually use a my digital camera with a tripod while standing up the LD cover up against a box on a table during the day (so a flash isn't necessary.)
Also, if you have photoshop, the perspective crop tool is indispensible to get the shot right . . .
Perspective Crop. . . I've also used that taking a picture of an LD at an off angle when I've had to use a flash (so the flash isn't reflected on the cover), but taking the pic without a flash is best.