it wasn't me who asked but i have the same problem, and CrashedAgain - thank you very much for the newbie-proof answer
unfortunately, it seems that i will not be able to use linux (kanotix) for a couple of days but i'm very curious:
it happens exremely often that when i download a .tar.gz and try to install it via synaptic it just doesn't see it. converting to .deb with alien doesn't help. using 'dpkg -i' only gets me an installed unpacked and uncompiled .tar.gz. sure, i have tried refreshing via synaptic.
is the 'dselect update' the solution? or is there something else i need to do?