If you're asking, is there a database where you can plug their name in, the answer is no.
70% of Americans die without active life insurance in force, so the easiest place to start, is with whatever it is that makes you think they even HAVE life insurance.
The second easiest, is to go through the banking records. If they had insurance, they'd be paying for it, at least once a year, but usually once a month. You should see a cancelled check. If you're executor/administrator of the estate, you can get copies of all their cancelled checks for the past year, from their bank, and go through them. Be sure to check the safety deposit box at their bank, too.
Obviously, you need to check through their valuable papers at their home.
If they were employed at the time of death, call the HR department at their employer's, to see if there was any group life insurance.
If you suspect they had a prepaid policy, just change the mailing address to yours - if they DID have a paid up policy, once a year they'd be receiving a statement from the insurance company.
Again, if you're executor of the estate, you can pay $75 to http://www.mib.com/html/lost-life-insurance.html and they will tell you if any applications have been received on their lives, in the past 13 years. It only goes back 13 years, and you'll need to send them proof that you are administrator or executor of the estate.
Don't be worried about someone else "intercepting" your life insurance money. If you are the beneficiary of the policy, the insurance money gets mailed directly to you.
If you're not administrator or executor of the estate, AND a check doesn't show up to your mail one day, then legally you don't have access to the information - it's protected by the privacy laws. But you can always ASK the administrator/executor if there is life insurance, and who the beneficiary is.
Life insurance tends to run in families. Do you have life insurance? Your sibs? Your parents? Most people TELL family members, if there is life insurance. If none of the surviving family members have any life insurance, odds are, the deceased doesn't, either. That's your PERSONAL reminder. Go buy life insurance, and tell at least two different family members that you have it, and where you keep your valuable papers.