Deductible business expenses can reduce your income tax liability this year. They include costs related to advertising, attracting customers, employees benefits, office space, and more. If you have deductible business expenses, file IRS Form 1040, Schedule C (for freelancers or small businesses), or Form 1040EZ (for individuals). Deductions are also available for interest paid on loans used to purchase books. You can deduct the interest on any loan that has as its purpose acquiring or producing books. The amount of your deduction depends on how much you paid for the books and whether they were new or used. If they're old books that you're not going to use anymore, then you should probably sell them instead of wasting money on storage fees. Finally, if you wrote a book as part of your job, you could possibly take a deduction for the cost of writing it.