Do you want to change the environment variables for all users, or just your own account? Files that start with a dot are not visible. If you want to see them, run the command "ls -a ~". You should see all the files and directories, including the dotted ones, in your home directory. In any case, don't make the changes in .bashrc - it is better to set them in .bash_profile.
Rubberman is correct. /home/username/.bash_profile is the place to set it.
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
# User specific environment and startup programs