Can you help me find a researcher for Deja Vu?

Here’s his bio on Wikipedia and if you Google his name you will find other articles about him. I would read some of his work before contacting him. If you want to start now, you could go to your local library in addition to searching on Google and try to find articles by him in some of their specific psychology databases. It would be a good project for you.

Never assume anything. Read the book first. (Seems like I’ve answered this question before…)

You must read the book first. It is much easier for an author to feel friendly talking to someone new if they have read his/her book. If you are going to talk shop with him it will be lots easier for you both if you understand references he makes about something he wrote.
Besides, it just seems polite.

You may find that the book answers the questions that you have. If you are searching for a fellow time traveler you are probably going to be disappointed, since he treats deja vu as a disorder.