A political subdivision of this State that, at any time, has the power to impose and collect a sales tax:

            (1)      May not thereby be construed to have the power to impose and may not impose a sales tax on advertising transactions or on advertisers at a rate or rates in excess of the rate or rates in a sales tax imposed generally on other business transactions or other businesses by the subdivision; and

            (2)      May not impose a sales tax on advertising transactions or on advertisers except as part of the imposition of a sales tax generally on business transactions and businesses in the subdivision.