415 ILCS 5/55.13
The Department of Revenue may adopt and enforce such reasonable rules and regulations relating to the administration and enforcement of the fee imposed by Section 55.8 of this Act as may be deemed expedient.
Whenever the Department of Revenue is required to provide notice to a retailer under this Act, such notice may be personally served or given by United States certified or registered mail, addressed to the retailer or taxpayer concerned at his last known address, and proof of such mailing shall be sufficient for the purposes of this Article. In the case of a notice of hearing, such notice shall be mailed not less than 7 days prior to the date fixed for the hearing.
All hearings provided by the Department of Revenue under this Act with respect to or concerning a taxpayer having his or her principal place of business in this State other than in Cook County shall be held at the Department's office nearest to the location of the taxpayer's principal place of business. If the taxpayer has his or her principal place of business in Cook County, such hearing shall be held in Cook County. If the taxpayer does not have his or her principal place of business in this State, such hearing shall be held in Sangamon County.
Whenever any proceeding provided by this Act has been begun by the Department of Revenue or by a person subject thereto and such person thereafter dies or becomes a person under legal disability before the proceeding has been concluded, the legal representative of the deceased person or person under legal disability shall notify the Department of Revenue of such death or legal disability. The legal representative, as such, shall then be substituted by the Department of Revenue in place of and for the person. Within 20 days after notice to the legal representative of the time fixed for that purpose, the proceeding may proceed in all respects and with like effect as though the person had not died or become a person under legal disability.
415 ILCS 5/55.13