You guys need to worship me for what I'm about to give you.
I've been an Ayu fan for 5 years, but for the past few months it's gotten a lot more 'intense' than it used to be. ANYWAY! I joined Ayu's biggest international forum, I get everything I know out of there, it's a fun place.
YOUTUBE is bad for Ayu videos, because Avex checks them out and always asks for them to be removed. On the other hand, I found two other websites, with ALL her music videos AND MORE to date:
Dailymotion - Share Your Videos
And this is my personal favorite:
JpopAsia - It's like... Jpop Heaven! XD
Just make a search for Ayumi Hamasaki and you'll find a list.
Also. You can find all kinds of downloads(that includes her most RECENT concert: CDL07-08) on the Ayumi Hamasaki Sekai forum. There are also threads with all her albums and singles you can download the songs. (Though please remember to support her by buying her DVDs and CDs, downloading should only be in the mean time, until you can get the real things~)
I don't want to post the forum link, in case that would be considered advertising. If you make a quick search on Google, you'll be able to find it :3