How can I find out what happen to my 401k, if the company was bought out. I left this job 10 years ago and I know I still had money in there.

You need to contact the administrator of the 401(k) plan. This is most likely a mutual fund company, or an insurance company, or a bank that your old employer contracted to run the plan for them. Ever since you first signed up the administrator has been sending you quarterly statements about your account, so you can simply look up the contact information on any of the old statements. If you moved and failed to notify the administrator of your new address, and if you don't have any of your old statements, then you need to become a bit of a detective to find out who the administrator is. Unfortunately there is no national data base of all 401(k) plans. So the simplest way to proceed is to call your old boss, or any other employees you may still be in touch with, and ask if they can tell you how to contact the plan administrator. If that doesn't work, you can try the National Registry of Unclaimed Retirement Benefits (NRURB). They are responsible with keeping over 50,000 individual retirement accounts for individuals who have forgotten 401(k), profit sharing and other company sponsored plan balances that have been abandoned:

www.unclaimedretirementbenefits.com/doParticipantSearch.m

The final suggestion is go on-line and search for abandoned property in the state you lived in at the time. If you have not been receiving statements from the 401(k) plan administrator they may now consider you lost, and by law they would have turned your assets over to the state. Every state has a program to try to reunite people with their lost assets. Here is a free web site that lets you search your state's database of abandoned assets: Missing Money Free Search for Unclaimed Property - Officially endorsed By The States (http://www.missingmoney.com). It's a good idea to do a search on every state you ever lived in to see if there are abandoned assets in your name.