Answer
This question was answered on December 21, 2001.
Much of the information contained herein may have changed since posting.
It looks like you have a lot of traffic, and too much clutter in your office to have network cables running through. But remember there are other alternative ways to having a network and they are inexpensive and fast enough for your local network to work properly.
Infrared technology in the networking area is not too bad. Alot of class rooms and homes are considering this technology because you don't have to drom cables and tear out walls. All you need is the infrared transmitter and reciever, hook them to your computer and then you are on your way to having a network. One vendor that is popular is Intel's Any Point.
I hope this gives you another option to networking your office.