Maybe this may help?
http://pavao.org/shadowrun/miscellany/dvc_enclave.pdf
Aaron has always been an awesome source of SR info....
But really, if you want info that can help you out, just google or drop by any major office complex in your home town and observe how and what goes down... Then dial up the paranoia and security

Some tips to remember:
1: Security has to be user friendly to be effective. The more the security interferes with normal operations, the more likely employees are to ignore or bypass it for their own ease of life.
2: Not every building is going to be "guarded to the gills"... Manpower costs major money... but so does tech and magic..... So companies look for a happy medium between Cost and Effectiveness. Sometimes that is a single guard at a desk and maglock key readers on every major door.... Other times that is roving drones, spirits and HTR teams 3 minutes away..
3: "Top Secret" facilities also mean no extra-territoriality... which means any security is going to be tight... but also hidden as the corp can't employ all their usual tricks