For further details, call Austell Gas at (770) 948-1841. Please fill the form below or, if you prefer, print and complete this form to send by mail (with your payment), fax or at the main office. Mail: Austell Gas System, Attn: Budget Billing, P.O. Box 685, Austell, GA 30168. Fax: 770-948-8644 â Attn: Budget Billing.