Great place to find unusual Bento’ish supplies was a local craft show, they had small Tupperware containers that held 1oz or 2oz. These will be great for sauce or dressing when I need a little bit more. Also, in looking in the Tupperware catalog, they had many containers that would work well as a Bento lunch container.
You can find all kinds of interesting foods and items at flea markets, yard sales and resale shops as well. Another persons trash is someones treasures. You can get most Tupperware at AMAZON.com, but for online deals and specials see the site below
The site I use for Tupperware supplies is : http://www.my.tupperware.com/sandramoore (just cut and paste into your browser)