A surprising number of people find HC USA while searching for the free PASS textbooks. I'm guessing this means they are still unavailable online in the "usual" places. If you want copies of these free books - they're in PDF form - you can still try this (taken from the old blog): You may request your free copy [of the CD-ROMs with the student and teacher editions] by sending your full name and mailing address to: BRIC@fldoe.org. You do NOT have to be a Florida resident to request these books. They cover mostly core subjects in middle and high school, with a handful of electives.
If that doesn't work, please let me know through the CONTACT page and I will edit this post and talk with you privately about how to get copies. (Perfectly legally! It's just something I have been asked not to publicly post.)