Use Mac ports to install SPE. But first deal with the Mac Ports dependency issues.
sudo port install spe
...
Error: Target org.macports.activate returned: Image
error: /opt/local/include/X11/extensions/render.h is being used by the active render port. Please deactivate this port first, or use the -f flag to force the activation.
Warning: the following items did not execute (for xorg-renderproto): org.macports.activate
Error: The following dependencies failed to build: libsdl xorg-libXrandr xorg-renderproto
Error: Status 1 encountered during processing.
The render port was removed a while ago, and for quite a while before
that it installed no files because it has been replaced by
xorg-renderproto. Anyway, render is no longer needed, so to get rid of
it just run `sudo port -f uninstall render`.
sudo port install spe
download the Mac dmg
http://developer.berlios.de/forum/forum.php?forum_id=13452
http://blog.jeffstieler.com/wp-content/uploads/2009/03/spe.dmg