I am actually working on a jelly roll quilt right now. I picked the heritage Moda jelly roll, and its fun. Its a great way to have a nice assortment of fabrics.
You can buy jelly rolls in many forms on ebay. You could buy a roll, with shades of blue, or green, etc. Just pay attention to what you are getting. Some homemade rolls may only have 10 or 20 strips, while the moda rolls have 40.