Past papers are now found in Moodle. To view the past papers for a module find it in Moodle and look for the Past Exam Papers block, usually towards the top of the page:
To view an exam paper click on its title and it will open automatically. If you can't find the block get in touch with your department who might not have uploaded any past papers for the module yet.
If the module doesn't have an exam as part of its curriculum, the block will display that there are no past papers available for this module.