Setup is simple.
These are the items I purchased to have what I thought was a proper setup.
I used these to mount the cameras on my ceiling.
http://www.amazon.com/gp/product/B002WN1GO...s00_i00_detailsI bought 2 of these, but in truth I only needed one. Important get this model not only because its inexpensive but because it is active technology which is integral.
http://www.amazon.com/gp/product/B004AGX4Y...s00_i00_detailsYour going to need a decent graphics card. An Nvidia 590, or 580 are the best and will process the tracking in faster than real time. However those cards are extremely expensive about $500.00
My solution was to get a 520. The processing is slow takes about 15 minutes to do a 1 minute shot. As for prices and bang for your buck my next option if you had money to spare would be the 560 but not any of the in-between models like 540.
http://www.amazon.com/gp/product/B004W3F9X...s00_i00_detailsThere are plenty of specials out there to get the 2 kenect cameras for $99.00 each. Keep searching. Do not pay more than $99.00 for the cameras.
To finally answer your question no you do NOT need anything other than the items I have listed above.
1 more tip. You can purchase the ipi software for $350.00 if you request that price specifically from Mr.Bones. However I recommend you get all your questions into him while you are using the demo and before you purchase as he will ignore your questions after you purchase.
Joe from Mr Bones is an interesting character. I find when I speek with him in person via skype he is extremely friendly and seems like a kind soul. However my dealings with him via email are the oposite. For example when I sent him a screen recording of issues I was having with the software and pointed out stuff I asked him to pass along to the developers because he has their ear he responded with "Stop complaining"