If the printer is listed there there is at least some support for it - but that doesn't necessary mean it is really usable.
A good source of information about printers in general is http://www.linuxfoundation.org/colla...s/openprinting
If a printer is listed as supported there it at least can be made working with Ubuntu, if it is not listed there or listed as unsupported it most likely doesn't work - at least not now.
For HP printers you can look at http://hplipopensource.com/hplip-web...ces/index.html You can see the version of HPLIP that comes with your Ubuntu version by
looking for the package hplip in Synapitcs or by
at the command line.
apt-cache show hplip|grep ^Version: