I downloaded this code and tried it on Fedora 16 x86_64, and it will not compile. It looks like some of the resources (libglib2.0-dev and libgtk2.0-dev, for example) go by a different name in Fedora (and I would guess other RPM based distributions) than in Ubuntu.
To install this package run on a fresh ubuntu 11.04 system:
sudo apt-get install build-essential lxde
sudo apt-get install libglib2.0-dev libgtk2.0-dev libmenu-cache1-dev
sudo apt-get install libsensors4-dev
sudo make install
On debian (and possible other systems) the package 'lxpanel-dev' is
sudo apt-get install lxpanel-dev
What I needed to install:
lxpanel-devel (which installs as dependencies libXpm-devel and menu-cache-devel)
gtk2-devel (which installs a number of dependencies:atk-devel, autoconf, automake, cairo-devel, fontconfig-devel, freetype-devel, gdk-pixbuf2-devel, libX11-devel, libXau-devel, libXcomposite-devel, libXcursor-devel, libXext-devel, libXfixes-devel, libXft-devel, libXi-devel, libXinerama-devel, libXrandr-devel, libXrender-devel, libpng-devel, libxcb-devel, pango-devel, pixman-devel, xorg-x11-proto-devel, and zlib-devel )
Once these were installed, the compilation via make/make install proceeded without problem and I now have visible sensors on my panel.