Misdelivered package, lying thieving neighbor

I ordered a 50# bag of diatomaceous earth online, for $27, plus $33 shipping, Fedex.
When it failed to arrive I contacted the supplier who told me their records from Fedex indicated it had been delivered last Friday, and "left in front of the garage"
The problem is, I don't have a garage, .
The big house on several acres directly behind me, acccessed by a long driveway alongside my yard, does have a garage.
I went back there today after work and spoke to the woman who lives there, who denied that she had found my misdelivered 50# bag, but then admitted that they did have a 50# bag of DE themselves.
I asked her where she got hers, she said "Ebay", but couldn't recall what it had cost.

I could vibe that she was lying to me, and had misappropriated my misdelivered package.
Fedex has been contacted by me and the seller, and will try to retrieve the misdelivered package tomorrow.

I can hardly believe this neighbor would lie to me to steal a misdelivered $27 bag of dog-flea repellant.
I think to keep a package addressed to me, as if your own, because it was erroneously left at your door, is beyond sleazy.
I can't believe this is some legal "finders-keepers".
It clearly had my name and address on it, if this neighbor's admitted-to bag of DE is the one not correctly delivered to me.
I believe she had a legal--and moral--responsibility to return it to me, if misdelivered to her.
I think she essentially stole it.
Does the law support me claiming she stole it?

"To appropriate lost or misdelivered property or services of another, or the value thereof, with intent to deprive him or her of such property or services" is a violation of criminal codes in some states, but apparently not in mine.
Any cops or lawyers out there who can offer me insight?
Thanks