You could try this:
FROM sysobjects so
JOIN syscomments sc ON sc.[id]=so.[id]
WHERE so.type = 'P'
and sc.text like '%INSERT INTO yourtable%'
It isn't 100% reliable (you can miss some procedure because of split into two rows, or because dynamic SQL is used), but it could help you to locate the procedure.
Other than that, Profiler is the best way to go, because it will monitor anything... and there is always a possibility that some rows are not inserted by the procedure but in some other way - and that's probably what you need to know.