I remember seeing this topic come up from time to time and came across a nice list in the Neo-Anarchists Guide to Real Life.

Bloch Security Services
Desert Storm Security
Fargo Security Providers
Hard Corps Security
Hartford Security
Jolly Roger Security
Knight-Errant
Len Grubb and Assoc.
Nightdancer Home Protection
Olympic Home Defense
Sydney Services
Wolverine Security
Zero-Zone Security

The list was nice, giving cost ranges, personnel quality ratings, astral and/or matrix security, etc..

There's another small company out of Texas, Lone Star.

I think vice have something like that.

So small, they devoted an entire sourcebook to it. *smacks forehead*

The list was private security providers. I think they considered Lone Star as security for the public by default in most locations.