(1) The department will make available to all businesses a guide regarding the process for filing an application under the one-stop program. This guide, as periodically updated by the department, may be obtained from the Department of Revenue web site at revenue.mt.gov; by a written request to P.O. Box 5805, Helena, Montana 59604-5805; or by calling the department's call center, toll free, at (866) 859-2254 or in Helena at (406) 444-6900.