I believe that technique is used a lot for walleyes in the upper mid-west. For the weight, I believe they use something called a Lindy that is available through Bass Pro Shops. It's a long skinny weight that is designed to slide along the bottom.
Just google for Lindy No-snagg sinker and you will find them.
Actually, I bought a couple at the spring sale and i plan on trying them, just wondering if anyone has already done it here... from my online research, this is the preffered way to catch lakers in canada.