Actually, you can keep Actions in any folder you want, anywhere on your hard drive (same with Styles, etc.) You access them by clicking on the little right-facing arrow on the Actions pallette tab, and then choosing "Load Actions" in the resulting drop-down menu. This’ll take you to the standard file browser where you’ll find and select the folder, wherever you end up keeping it. From there, of course, choose the Action you want.
Now, that aside, the PROPER place to keep Actions is in the Photoshop application folder=>Presets=>Photoshop Actions. To load an action once it’s placed there, following the same procedure above.
the PROPER place to keep Actions is in the Photoshop application folder=>Presets=>Photoshop Actions
That is certainly the easiest location to put them and is fine if you want all users to be able to use your actions, but you must remember in the future to back them up before upgrading Photoshop.
I tend to put custom files into my Documents folder; I created a Photoshop folder for this purpose.
The bottom line is that you can choose whichever folder suits you best.
