This product will not work. It only has 2 outputs, and you have 3 TVs, so this isn't it.
This product will work.
What you want is a splitter. Think about it - You need to SPLIT the HDMI output to three different TVs.
The OTA signal, I assume, is coming directly to the televisions, so you would just switch from your HDMI input, to the local TV tuner input, and watch TV.
There are solutions which allow you to use multiple cable boxes, another HMDI source, and the Blu-ray player with your 3 TVs as well, and it is identical to the first product linked above, but a bit larger...
That has 4 inputs on it which allows you to connect up to four different sources. For example, a cable tuner, a PS3, a AppleTV, and your Blu-ray Disc player.
Then, you can connect up to four TVs. You only have three, but it has room for up to four.
Each TV can watch any of the four sources however they like. So, TV 1 can watch Blu-ray, TV 2 could watch cable TV, and TV 3 could watch AppleTV. If TV 1 wants to watch cable TV as well, then both TV 1 and TV 2 would now be watching cable TV.
The downside is that the image will flash off and then back on as copyright protection is authenticated across the displays and sources (HDCP).