directory alias

[shawn wilson <ag4ve.us@xxxxxxxxx>]

not sure if this is really a 'zsh thing' but I'm looking for a way to
create aliases for a command. I don't want a bunch of symlinks in my
home directory, and I don't want a universal alias for each directory
I commonly cd into. What I want is a way to do:
cd foo
and it go to ~/some/deep/directory/tree/foo
and
cd bar
and it go to /usr/local/some/path/bar

Is there some zsh-ism (or better bash-ism that also works in zsh so
that this works on systems I maintain without zsh) to do this without
symlinks?