I never find the info on how to change the Debian console keyboard layout. Here are some ways (with Estonian as an example):
- 
dpkg-reconfigure console-data
 - 
install-keymap et
 - for a temporary change –
loadkeys /usr/share/keymaps/i386/qwerty/et.kmap.gz
 
loadkeys et
is sufficient.
However, with Dvorak layout loadkeys gets confused and complains something about flex scanner. To get it to work, load Dvorak with
loadkeys dvorak/dvorak