| Business | Phone |
| United Software Inc 130 S Il Route 83, Grayslake 60030 | (847) 223-1874 |
| Tartec Development Corp Grayslake 60030 | (847) 548-5272 |
| C D Rom Productions 100 S Atkinson Rd 215, Grayslake 60030 | (847) 986-3790 |
| Parkinson Systems Inc 355 Buckingham Dr, Grayslake 60030 | (847) 548-1376 |
| Hawkwa Group 26 Hawley Ct, Grayslake 60030 | (847) 687-0493 |
| Insight Enterprises Inc 1083 S Corporate Cir D, Grayslake 60030 | (847) 543-4444 |