Alternative for Mac OS X Automator?

There is Gnu Xnee, which enables you to record and replay actions on the desktop. You can install it from the software center.

"GNU Xnee is a suite of programs that can record, replay and distribute user actions under the X11 environment. Think of it as a robot that can imitate the job you just did."

If you're feeling adventurous, you could try out Sikuli. It's a computer-vision-based, cross-platform GUI automator with a slick IDE. It wasn't developed on Linux, so the Linux documentation is a little thin; however, it's pretty intuitive, and most of the non-Linux documentation applies.

Well, there's xnee and its version with a GUI gnee.

You can find it in the software center or install it via

sudo apt-get install gnee

Screenshots and documentation are available on the GNU xnee page.