From HMV.com (UK):
To celebrate the release of Stargate Continuum on DVD and Blu-Ray on 18th August 2008, we've teamed up with our friends at 20th Century Fox to offer you the chance to win a signed copy of the script. Simply fill in your details [at the site] to be in with a chance of winning this great prize.
A brief excerpt:
To be eligible, entries must be received on or before the closing date of 1st September 2008 11.59 PM GMT
And there is a brief video clip of Amanda Tapping, announcing that Continuum is available for pre-order from HMV.com, that precedes the Continuum trailer, at the site!