| Business | Phone |
| Building Industry Assn 1330 Valley Vista Dr, Diamond Bar 91765 | (909) 396-9993 |
| Diamond Bar Country Estate 22615 Lazy Meadow Dr, Diamond Bar 91765 | (909) 861-4114 |
| Ymca 22600 Sunset Crossing Rd, Diamond Bar 91765 | (909) 860-9622 |
| American-Chinese Economics 810 Coldstream Ct, Diamond Bar 91765 | (909) 396-8999 |
| Diamond Bar Improvement Assn 1081 Grand Ave, Diamond Bar 91765 | (909) 860-1008 |