| Business | Phone |
| Arrow Creek Resources Inc 208 N 29th St, Billings 59101 | (406) 690-8100 |
| E Earl Norwood 121 N Broadway, Billings 59101 | (406) 252-9661 |
| Enthalpy Inc 115 N 28th St # 318, Billings 59101 | (406) 252-3685 |
| Don E French 2812 1st Ave N # 417, Billings 59101 | (406) 245-7840 |
| John E Grauman Jr 2812 1st Ave N, Billings 59101 | (406) 254-6521 |
| Henry E Reed Geological 3203 3rd Ave N # 306, Billings 59101 | (406) 245-8880 |
| Highline Exploration 2812 1st Ave N # 430, Billings 59101 | (406) 294-6222 |
| Gary C Hughes 3203 3rd Ave N, Billings 59101 | (406) 248-8966 |
| M J Adams Consulting Geologist 2254 Darcy Ln, Billings 59102 | (406) 652-8202 |
| Jones Mk-Petroleum Geologist 1832 Arcadia Dr, Billings 59102 | (406) 652-4505 |
| Langdon G Williams Petroleum 490 N 31st St # 205, Billings 59101 | (406) 252-2070 |
| Larry Geisler Inc 2812 1st Ave N # 211, Billings 59101 | (406) 256-6353 |