Why the "but"? Wal-Mart, Home Depot, Lowes or even Harbor Freight sell a wide range of tool boxes at reasoanble prices. What so different about bike tools that they need a special box?

As to purchasing the tools themselves, Bike Tools Etc. is an excellent source. Also, most of the big on-line bike and component retailers like Colorado Cyclist, Nashbar, Jenson and Amazon carry a range of bike specific tools.