If you lived in Illinois all year, your employer should not have withheld Wisconsin taxes. If you haven't already done so, you should submit Wisconsin Form W-220 to your employer. Here's a link to that form: https://www.revenue.wi.gov/DORForms/w-220.pdf
Illinois and Wisconsin have tax reciprocity. If you live in Illinois, and your only Wisconsin income was W-2 wages, ordinarily you would not have to file a Wisconsin tax return. All your income is taxable by Illinois. However, in your case you WILL have to submit a non-resident Wisconsin tax return for 2017 - in order to get a refund of the mistakenly withheld Wisconsin taxes. Your Wisconsin return should show zero Wisconsin income.
If your two W-2's split your income, you should enter each one into TurboTax.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
