My mom got the pattern for this organizer from Stitch 'N Bitch: The Knitter's Handbook by Debbie Stoller. It is a great book for patterns, as well as to learn basic knitting techniques.
If you are looking to make your own organizer, check out this DIY guide from the blog Made by Loulabelle.
There are also some adorable knitting needle organizers on etsy. I'm particularly loving this one from sarahkincheloe -- even though this one is for crochet hooks :).
I took some time to organize my yarn today, which I keep in this great basket (another gift from my Mom!)