My Mother died a year ago but some of her estate money cannot be found--I am the POA of her will -- is there a website where I can get help to locate the bank,investment, or insurance company

No - there is no single web site that has this information. How do you know that there is money that you can't locate? You say you are "the POA" - do you mean you are the executor (or personal representative, as it's called in some states)? If so, then I suggest you proceed as follows:

1. Search through your mother's financial papers - if the money was invested in a bank or financial institution she may have kept old statements.

2. Watch the mail as it comes in over the next few months - if she has an active account they should be mailing out statements monthly, or at least quarterly.

3. If this account has any interest or dividends that it is accruing they should have sent out a 1099-INT or 1099-DIV form to her last January - have you checked through last year's tax records for this?

4. Have you gone to her local bank? She may have a safe deposit box there, and in it you may find important papers, CDs, savings bonds, etc.

Can an attorney run a social security number and find stuff like this?

Can an attorney run a social security number and find stuff like this?

No, but the IRS may be willing to provide a list of accounts that have had income reported for that SSN to the appropriate person.

As an aside, generally a POA expires at death. So its more likely you are the executor or administrator of the estate.