I am very used to using Ctrl + A, Ctrl + E, Ctrl + L, etc. as shortcuts to operations (beginning of line, e
Check for vi mode (set -o) or a vi editing-mode or keymap (bind -v). The default mode is emacs, but it might be set to vi e.g. in ~/.bashrc (with set -o vi) or ~/.inputrc.
In that file if you want the nauseating emacs voodoo bindings instead of sweet, clean vi:
set -o emacs set editing-mode emacs
In the above, remember that emacs mode is the default, but you never get hurt by being explicit...
Again, you said you were using bash, so run:
bind -p
at the shell prompt to ensure that you have the bindings you think you have
finally, since it's OSX, check to make sure you have the readline library ( which is how you get all this stuff.) Again, it should be there by default, but perhaps it is not.
Check the TERM setting in the Terminal.app program ( Preferences > Advanced > Emulation )
The fact that your rig works when you ssh somewhere else means implies a local problem.
Good luck.
My leopard works out of the box with ctrl+A etc...
I think you've somehow got the ctrl key mismapped. You're not using the command, or alt key, right?