Here is a list of the current available magazine covers that featured Madonna, hope that these can be of some help to your
collection:


Life:  12-86 "That Fabulous Couple: Madonna and the Camera" $29.95

Rolling Stone  11-22-84 Madonna goes all the way  $34.95
Rolling Stone   9-10-87 Madonna on being a star.  $29.95  pen mark on cover
Rolling Stone   3-23-89 Candid talk about music,movies and marriage  $29.95
Rolling Stone   9-21-89 Madonna with Camera  $24.95
Rolling Stone   6-13-91 Big time girl talk. Madonna on chair spread legged
$34.95 
People 6-25-90   Madonna on cover with Warren Beatty (Dick Tracy) $19.95

TV Guide (small format)11-23-91  Good Picture, "Madonna on TV." - $15
TV Guide (large format)11-23-91  same as above  $20

People:
        4-15-91, very good picture with Michael Jackson $19.95
        12-16-91, best and worst dressed, medium size picture- $19.95

Entertainment Weekly, 5-11-90.  Madonna Strikes a new pose  $24.95
Entertainment Weekly 5-17-91  Naked Truth Madonna on her New Movie $29.95

Vanity Fair October 1992  Hard to find.   $39.95

Premiere 7-90  Madonna and Warren Beatty  $29.95