Hi Michelle. I've done lots of research into this area. I don't think there's anything that everyone would agree is "proof", but there are interesting circumstances and people.
First, depending on your religion, you may believe in certain stories of the dead visiting the living.
Second, you're not alone in your interest - several people explore what happens after death and even make a living doing so. I'd encourage you to research specific topics as you see fit but here's a fairly short video of a woman who accurately guesses several aspects of a man's life; controversy remains as to whether it's a skilled performance or genuine reading.
Third, feel free to ask people you know! A good friend of mine's father swears he was visited by a ghost in a hotel once.
Finally, I'd recommend a book called the Afterlife Experiments if you want a more in-depth analysis of someone researching death.