Recommended and introduced by Trevor here.

Each book (one for each level of the new HSK exam) contains ten practice exams including a companion CD containing mp3 of the audio portion of the test. After taking all the practice exams you may extract further value from the book by using the “Truncate Silence” effect in Audacity on mp3 files to get rid of the pauses in the audio portion of the test and use the resulting audio as listening practice. Although notoriously harder than the corresponding offical HSK exams, these simulated exams still feature many relatively high frequency vocabulary dialogues providing good comprehensible input for beginners.