M$ provides an excellent FREE resource I used often in becoming certified in Office -- Note, you will have to use IE or with FoxFire the "IE Tab" add on, because M$ will only do any downloads with IE

Another excellent FREE resource I used is YouTube--some videos are clearer than others -- In your case, pay attention to this dude calling himself Mr Excel -- He is annoying in his hyper presentation, but he does explain well and offers a FREE work book