| Business | Phone |
| Challenge Sales 2678 Bishop Dr # 120, San Ramon 94583 | (925) 277-3131 |
| Advanced Systems Assoc 7528 Corrinne St, San Ramon 94583 | (925) 373-6078 |
| Magnolia Hi-Fi 110 Sunset Dr, San Ramon 94583 | (925) 242-3600 |
| Radio Shack 3191 Crow Canyon Pl # I, San Ramon 94583 | (925) 355-9218 |
| Teletrac Inc 2303 Camino Ramon, San Ramon 94583 | (925) 543-0900 |