Mouse locator is what you are looking for. The requirements are:
Universal binary compatible with both PowerPC and Intel processors. Requires Mac OSX version 10.4 (Tiger) or later. (321KB)
so it will work with you. This uses a shortcut as a trigger to 'ping' the cursor's location or a timer (in trigger delay) to show the cursor location.
You will be able to find your cursor very easily with this:
Highly visible locator instantly reveals your mouse position.
It installs this as a separate System Preference Pane.
These are all the options you can change:
I would recommend using F5 as the shortcut key because it is generally used for nothing on the Mac (by default)
If you want, you could also make your cursor slightly bigger, but this could be annoying, maybe covering words or letters when doing other stuff, but there is always the option!:
You’ll find the setting within the Universal Access pane of System Preferences (Apple menu->System Preferences). Click the Mouse & Trackpad tab and then click and drag the Cursor Size slider. The changes will take effect immediately, so choose a size you’re happy with.
Read more over here