They have some instructions on their website to enable a new PPA to use the software center or apt-get to install, with what you downloaded though I would guess you need to build the package so this should do it (I am assuming you have the tar.bz2 file in your ~/Downloads folder, you will need to change the code accordingly). This should work, but I'm not on a computer I can look at it good with so I can't be fore sure.
in a terminal you will use these commands...
to get into your downloads directory
to unpack it (I think you have already done this, but thought I'd throw it in there)
tar xvf iplist-0.29.tar.bz2
to get inside the iplist source folder
to set up your build configurations
to build the package
to install the package
You will need to keep the package up to date building form source like this yourself as the package manager will not know it's there, so adding the PPA is probably the better way, but building it should install it. Also you may need to install some packages to use make, I'm not sure exactly which ones on Ubuntu though.