how do i find my father?

I assume there is some reason you don't want to speak to your mother about this, aside from the fact you were sneaking around in her handbag. Do you know his full name? Have you tried on-line or old fashioned phone books? If he drives, the information on his driver's license is public information (at least it is in the US) and you can go to Department of Motor Vehicles office and look it up.

I would first suggest you confront your mother and get her side of the story.

Did he write his address on the letter?

I don't believe you have posted enough information for us to be of much help.

How old are you, and how long has it been since you have had contact with your father?

Is your mother still alive?

Is your brother older or younger and does he have any recollections you don't?

Do you have any other, older, family members that might be able to help?

When was the letter written, and what information was there in/on it?

What means have you tried? Sometimes just Googling his name ans expected location will get a hit.

Is the information you seek private, sensitive? Have you thought about posting what you know about your father so that others can search for you?

Fill us in and we'll see if we can help!

I don't see why the majority of these questions would be helpful in finding someone or that the answers are really any of our business. I don't think this person should post any names as perhaps the father is not looking for the public to know his business and might get very angry to know his identity is being revealed to strangers on the internet. There are public records this person can access if she is old enough or best yet, if the mother will cooperate.

You don't think that it makes a difference whether the poster is 12 or 72?

Whether there is a mother to quiz is irrelevant?

The letter was written to the brother, but it makes no difference if he is 10 years younger, or 10 years older (and remembers dad as a creep/saint)?

Other, older family members that might have had interaction with Dad are irrelevant?

It make no difference if the letter is 2 years or 50 years old? Or if there was a return address on it or contact information in it?

Knowing the free information she has accessed isn't worthwhile?

If the father is very angry that the daughter tried to find him by name on the internet, is he worth finding? If we don't find him, how would we know? If his "name" is his "identity", then let him run.

You need to ask your mom. You need to tell her that you found the letter and that you have questions.

I know it might be really hard to do that but there might be a very, very good reason that she doesn't want him to contact you (or vice-versa).

Ask her.