You want to know when your Fingers of Frost or Fireball! buffs are procced so you can change your game play.  But during a raid, with all of the buffs, it can be difficult to notice.

There is an addon called 'Parrot' that you will want to get.

Parrot is basically an uber version of scrolling combat text.  It puts all kinds of combat messages on your screen.

The downside is that it can clutter up your screen in a hurry.  The upside is that it's highly configurable, including allow you to create custom notifcation messages, such as when your Fingers of Frost or Fireball! triggers!

Once you download and install it (I use curse.com's tool for auto-downloading),  you'll want to configure it.  Without going into all the details, you'll probably want to turn off a whole bunch of the notifications.  (Uncheck the 'Enable' box for each notification type.)  You can also use the Throttle section to set threshholds of what you want to see...for example you might not want to show each little DoT tick, so you can set it to display only damage done over, say, 300 points.

But the real magic is in using the Parrot mod to create your own  events.  Under the Events section, create a new event.  Configure the trigger to be when you receive a buff.  You specify the buff (Fingers of Frost for one, and Fireball! for the other....and you need the exclamation point because that's what the buff is named).  Then you enter the notification you want to see, like "FROZEN FINGERS" or "FIREBALL NOW, NEWB!", and select the 'sticky' option.  This will display your new notice prominently in the middle of your screen.  You can even add sound effects!

So hopefully this will help you track which of your buffs are proccing and you can adjust your play accordingly!