If I have some work expenses, where do I list these?

If you are self employed you deduct your work expenses on Sch C. 

If your "work expenses" are for your self-employment, you enter them under Business Income and Expenses.

If the "work expenses" are for a job where you are an employee (you get a W-2), they are not deductible on your federal tax return. A few states allow a deduction for employee job expenses. If your state allows the deduction, enter them in the federal Deductions & Credits section, under Job-Related Expenses. If your state does not allow the deduction, do not enter job-related expenses anywhere.