The 30% has been updated to 40%!
From Syngress:
“Now through August 15th, Elsevier is offering 40% off all their books, including X-Ways Forensics Practitioners Guide (use this link: http://store.elsevier.com/product.jsp?isbn=9780124116054&_requestid=665676). No promo code needed. Just follow the link, add to your cart and save big”
https://xwaysforensics.wordpress.com/2013/08/05/some-bad-news-and-some-good-news-on-the-xwf-guide/
The X-Ways Forensics Practitioner's Guide/2E 
That’s nice, but how do you use the code if you’ve already preordered the book?
We are only the laborers/writers of the book…pricing and discounts by Amazon, Barnes & Nobles, Syngress, and others is a wee bit out of our span of control…
Oh dear – have I missed the boat on the first printing run? The Elsevier link shows no results and Amazon still shows the book unreleased until September (Amazon.com) or October (co.uk). I knew I should have pre-ordered it!
It’s still there. You don’t need a code for the discount. Contact Elsevier if you have any problems, they will fix it for you if anything is not working.
hmm I’ve followed your posted link and also search every variant of the book name in the site in Firefox and IE – I’ll ask them. Maybe I’m blocked as an Aussie from seeing it.
Send a note to the publisher. They will respond quickly and fix any problems.