(Originally published in April 2008, and updated continuously since. Last updated March 2011.)
A very frequently asked question is where and how to buy the bento items and boxes mentioned here, especially in the Bento Item Spotlight (formerly Bento Item of the Week) feature, as well as on other bento blogs and sites. I've listed you several options, which I hope will be useful.
Look locally first
As much as I love online shopping, I believe in shopping at your local stores first. You're supporting your area's businesses, and you don't have to pay shipping costs. Besides, it's arguably a bit better for the environment (especially if you take public transportation!) since the goods have already travelled to your area.
You might argue, "but I don't have any stores near me that sell bento stuff!" I don't either. But it's always possible to find alternatives for lunch boxes, dividers, picks and other accessories. As I wrote in one of the earliest articles on this site, it's not necessary to buy a box that is labeled as a Bento Box in order to bring bento lunches. You can use cupcake cups, paper or silicon, as bento dividers, picnic utensils, and so on. Check out the Bento Gear Flickr pool for a lot of creative ideas from fellow bento enthusiasts.