A single-member LLC is considered a "disregarded entity" for purposes of filing a Federal income tax return. It is treated exactly the same as a sole proprietorship. The single-member includes all the income and expenses of the LLC in his or her personal Federal income tax return on Form 1040 reporting them on Schedule C.
I am not familiar with Wisconsin tax law so you should check with local sources on how this is handled. Many states start with Federal AGI which means that the Schedule C information is usually already included in this starting point.
