This has been discussed before. Lost and Found at EWR is atrocious. There seems to be no way to file a report and get something back, even of little value to someone who might take it. Although I'm sure some high value things are stolen, I think that the system is such that they don't really try and match the stuff they have against callers. They're not even interested in knowing what flight you were on.

I use to travel MetroNorth commuter trains between Grand Central and Scarsdale daily. Over the years, I probably left stuff on the train at least a dozen times ranging from raincoats to umbrellas to cell phones and briefcases, and I don't think there was more than once or twice that I didn;t get my stuff back. They had a central Lost and FOund at Grand Central. Everything was tagged by train # and date, and even prior to being computerized they had a card system that was able to match you up with your lost item if you knew what train it was lost on.