Sadly, I haven't watched many things in the way of music videos in the past year. Shame on me, I know...
However, I remember some of my favorite vidders, so maybe that will give you a place to start
I highly reccommend anything by LaraMoon, BanAnna, Psychofurball, Mmmsquirrel, Kltpyxym.
If you wanna show her a well-made fic trailer for an awesome series, carolm also just made a
fanfic trailer for Nan's Home series.
Gah. There are so many awesome vidders out there, and my brain can't remember them all
You can also search old
Alt-Kerth winners and nominees to find some awesome vids to show your friend.
This is a very good question XD I'll hafta keep it in mind, and come back when I can think of others
ETA: Don't accidentally click AddPost (or whatever it is XD) when you're trying to add a URL. It kinda throws off your posting groove :p