It looks like they changed their web site.
http://www.guitar-pro.com/en/index.php?pg=product has the new trial.
when trying to download the GUITAR PRO 5.2 edition, upon clicking the download now link an error screen says "server not found" even though my internet is working properly. i have vista 32 on a dell 1420 inspiron. other downloads from this site function/download properly. thank you!!!