| Business | Phone |
| Rupert A Brown 5323 Brook Way, Columbia 21044 | (410) 997-5331 |
| Convergent Communications 6301 Stevens Forest Rd, Columbia 21046 | (410) 910-5100 |
| Genesis Telecommunications Inc 6207 Deep Earth Ln, Columbia 21045 | (410) 312-2991 |
| Mesa Communications Group Columbia 21045 | (410) 799-7882 |
| September Nine Media Po Box 2803, Columbia 21045 | (443) 285-0999 |