Weed burning tools are often available at your local hardware store, home center, or independent garden center. Internet sources include:
Harbor Freight Weed Burning Tool
This tool is perfect for quick de-icing and weed control. It attaches to a standard 16 oz. propane bottle to give you portability that you can't get with other torches. It has a piezo push button starter, has a 24-1/2" long wand with a pistol grip handle. Sells for about $25. Go to Harbor Freight\'s Web Site
Brookstone Weed Burning Tool
Brookstone offers a Weed Burning tool for about $35. Eliminate weeds quickly and permanently with a propane-fired weed burner. Use this lightweight burner to clear weeds and their roots in driveways or walkways in summer, or to melt dangerous ice patches in winter. It is made of durable, nickel-plated steel. The brass burner uses widely available standard 14 oz. propane tank (not included). Adjustable regulator valve lets you control flame intensity. 32" L. Available in the Brookstone Catalog or one the Internet at Brookstone’s Web Site
For a larger system using the standard barbque type propane tank check out Weed Dragon Weed Burner
Using Weed Burning Tools
For tips about how to properly use Weed Buring Tools, go to Hand Weeding in Yardener's Problem Solver.