The best tire truing sticks are made by Mike Saputo...Mico Racing Enterprises!
He makes two grades, fine and coarse carbide.
Shop @ 314-869-3232 (message only)
Fax @ 314-869-8769
You guys are right this is the file you are looking for. Mike is the guy to buy it from. All the guys that race around here have these. Mike has been racing the HOA series that runs at my track and most of the guys around here have bought them directly from him. I suppose that it would be a bit cheaper to get it direct from him than through murdock. Personally I wouldn't buy anything from murdock myself.