Intellect requires no special network setup to use shared databases. Instead if the data is already shared and available on the network, you will only need to tell Intellect where to find it.
In the case of a shared and common telephone book, where you still want to have your own separate, personal appointments and to do items, you need to go to Tools, Options, then Advanced Data Paths. If you leave these paths empty, it will use your current location for all databases. However, for a shared telephone book, you should go to the Contacts field, click browse and find the ~phone.isd file on the network that you wish Intellect to use instead. Once selected and saved, you will need to restart the software for this to take effect.
Please note: I highly recommend that you ensure that the paths that you specify as Advanced Data Paths all begin with \\ (two backslashes) and not a drive letter. Drive letters are not universal across your network in many cases; where \\ paths are.
As you can see, these advanced data paths give you the ability of having a shared phone, task, or appointment database and the ability to keep those databases in any shared location you can browse to.
This help article applies to Intellect 3