Runescape: Pyramid Plunder Help???!!?

Where do you by the ticket to Sophanem? After I got to Pollnivneach the magic carpet wouldn't take me there. I read on Sal's Realm of Runescape that you buy a ticket there. http://runescape.salmoneus.net/pyramid_plunder.html. But where do you go to buy it??? HELP PLEASE. if you have 99 thieving add me please if you want because i would like some guide dense a little. i have 86 thieving btw(: