I am currently using Elementary OS with which I am testing all my tutorials.

First of all you need mercurial. For more information about mercurial see here: https://help.ubuntu.com/community/Mercurial.

$ sudo apt-get install mercurial

Then install v4l. For more information about v4l see here: https://wiki.ubuntuusers.de/v4l-dvb/.

$ sudo apt-get install v4l-dvb (with a small "L")

Then install the firmware. Hauppauge WinTV Nova-T Stick should be included in the package linux-firmware. For more information about the firmware see here: https://wiki.ubuntuusers.de/Hauppauge_WinTV_Nova-T_Stick/.

$ sudo apt-get install linux-firmware

To test if it works enter the following in the terminal:

$ dmesg | grep dvb

You should get something like:
[ 35.028736] dvb-usb: found a 'Hauppauge Nova-T Stick' in warm state.
[ 35.028774] dvb-usb: will pass the complete MPEG2 transport stream to the software demuxer.
[ 35.438352] dvb-usb: schedule remote query interval to 150 msecs.
[ 35.438355] dvb-usb: Hauppauge Nova-T Stick successfully initialized and connected.
[ 35.438611] usbcore: registered new interface driver dvb_usb_dib0700

You need of course an application that can stream DVB like Kaffeine or Gnu-TV. To search channels you need dvb-apps.

$ sudo apt-get install kaffeine dvb-apps