One way of dealing with the data preparation part of your task is through an application such as Datawatch Monarch.
You can easily drag in data from different websites into Monarch's Data Prep Studio, and then append, transform, and/or combine your data into a single recordset which you may then export to a Tableau data file, ready for creating your network diagram in Tableau.
Here's a video to illustrate a bit: Monarch Use Case - Web | Datawatch Community
You can try out Monarch for free here: http://www.datawatch.com/monarch-free-offer/
We have a release coming up very soon with lots of new features as well.
Datawatch is an official partner of Tableau Software.
Hope this helps,
Thank you for your reply and recommendation. I looked around on the product website and was not able to find any pricing. I would like to know how much it would cost prior to trying it out. If my company cannot spend funds on the program, then I shouldn't even use the trial. I hope you understand.
Totally understand. We offer subscription pricing.
May I have your email address please to send more info?