If he is a poor misguided dupe who has been fooled into selling stolen bike parts the least we can offer to do is get them back to the rightful owner.
I think visiting this individual to express our sympathies with his dreadful plight would be well worthwhile and a very christian thing to do. Something along the lines of: you hold the little sh*t while I smash his kneecaps with this 5lb lump hammer I just happen to have found in my car !!!!!
[Edited on 6-11-2005 by Paul James]