Hi. All my PC's and laptops are connected through a secure wireless access point. How do I play FSX on all machines with each user flying a, say, different airplane, so that we can all see each other flying around - to fly information for example? Thank you.

You need FS (Delux or Gold)installed (with service packs 1 and 2 or Acceleration) on all computers, then connect either through the LAN option or one of the available online private servers

and... I believe you have to use your internal IP addresses for each computer (often 192.168.X.X)