You could have simply asked "do you have any of my mail by chance as I did not receive it and I got yours" or something along those lines. Another way to do this would have been just to grow some balls and talk to her.

Trying to live out "seeking a friend for the end of the world"

If this is true, you asked for it. Mailman shouldn't have done it either because it's illegal.

Maybe your 'friendly' mailman decided (quite rightly) that it'd be funny to tell her what you'd gotten him to do, to see what happened. If that isn't the case, next time why not try going over and just introducing yourself? "Hi, I'm ____, I just thought it a little strange that we're neighbours and still don't know each other, so I thought I'd introduce myself :)". Not that hard is it? No more awkward than "Oh hi, you have my mail".

now youll have to go through her trash to see if its there good luck with that :/

Agreed! Props to the guy for being creative. Don't most girls complain that guys aren't creative enough?

She doesn't know he did that.

The best laid plans of mice and men....

Was your paycheck in the mail? If so she is a gold digger.

mom said that dont speak with stranger ,it's dangerous. look at you, kind of badboy