In GTA 4, you can call the services:
Grand Theft Auto 4 (GTA IV): Phone numbers (not codes) Free Download
Bean Machine Coffee – 555-0110
Emergency Services – 911
Express Car Service Roman Bellic “Enterprises” – 555-2222, 555-3333
Fire Proof Doors – 555-5700
LCPD Recruitment (Police) – 555
Liberty Construction – 555-1274-73
No Problemo Bail Bonds – 555-945-733-92
The Serrated Edge (CNT Show) – 1-800-555-5555
Storage – 555-221-3877
Superb Deli – 555-4674
Used Auto Part – 555-7300
Vinewood Laundromat – 555-5123
ZiT – 948-555-0100
You can also call people:
Romans Cell Number – 718-926-7215
I did not check it myself, a friend threw a chip!