Intarsia help needed

After seeing a picture of a bag on here that someone knit for his sister I decided it would be perfect for my sil. I have watched the video and it is still clear as mud. Well not quite that bad. But I am still very worried about buying the yarn and not being able to do it. Is there a book or another video I can watch that it explains it again? I would kind of like to have an idea when I start bugging my lys ladies left and right. It is a good thing they are so sweet.
Thanks Everyone

This is a good site.


Thank You So much the link. It helps me a lot.[/COLOR][/B]