have you bought NL before? If you had bought NL before, You should have gotten an e-mail with a link to the site for buying 1.6 with discount.
If you had bought NL before BUT AFTER the 1st of july 2006, then you should get an e-mail, with a free download from the 1.6 update.
If you never had bought NL before, just go to
www.nolimitscoaster.com and buy it. You'll just buy it like anyone else. It's automatic the 1.6 version. It's $29,95 But it's defenatly worth it!
Good luck [:)]