The start of term can be an expensive time for students and course books generally get pushed further and further down the shopping list, especially the expensive ones. So, the university has setup a marketplace for students to sell their no longer needed texts, where the buyer pays less and the seller gets more. Sound good?
Take a look at the Books on a Budget page and see if you can get kitted out. Failing that Oxfam Bookshop on Glossop Road (West Street) is well stocked and there's always Amazon's second-hand sellers on hand to snap up a bargain from.