I changed my son's name when he was 2 years old. It was really easy. Just go to "We The People" they have offices all over southern california. They are a legal documents firm where you pay them a couple hundred bucks and they give you the legal forms to fill out for changing the name, then you return the forms to them when you are done filling them out. Pay some money to run an ad in the local newspaper reporting the name change (required by law) and then after that if no one comes forward to protest the name change you will have a court date where you go in to court to affirm the name change and that is all.
I think you will have to pay We The People a fee for their service, and then you will have to pay to run the ad in the newspaper, and then you will have to pay a court filing fee. It should cost you around $300 bucks to do it all, which is cheaper than an attorney.
You can look up We The People online to get their address and phone number although if you tell me where you live I can look it up for you.
It should take less than 6 months for the whole process. The important thing is to get the paperwork turned in as soon as you can to We The People and then get the ad running. Also don't miss your court date as that will also delay you.