OK - an off-the-wall question here re: Firefox Bookmarks

Hello all:

Hope you're doing well! I have a question here that's been driving me up a wall and I know there's a simple answer for this.

It involves Firefox browser bookmarks cache. I use Firefox exclusively (currently am using version 3.6.12). I'm also using the X-Marks bookmarks protection service - which unfortunately expires (goes out of business?) in January. For those of you who use X-Marks, you know that this awesome syncronization plug-in really makes life easy by backing up all your bookmarks on their X-Marks server. But with them going out of business, I wonder what else will be available. As it stands now, I have almost a thousand different sites bookmarked.

But in the meantime, my question is, "where on my PC would I find the current Firefox bookmarks info so I can just save that file separately from time to time - so that if my PC crashes, I can import this file when I reload everything and be able to save my bookmarks. It used to be easy to do with IE bookmarks - but never so with Firefox (well, for me that is).

I'm running Windows 7, 74 Bit system. So where should I look on my "C" drive - meaning, folder, etc., to find the Firefox bookmarks? I've been unable to locate them at all. And of course, what are the bookmarks cache file called so I can identify them?

Any valid help here would be appreciated as I've tried searching endlessly for this file - but to no avail.

Thanks...
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