how do you find out information/personal details/ data on a person online? they do not have a facebook account to my knowledge, ive checked, and i do not know their email or phone number etc?

can u find that online and if so how?

any tips/advise?

You might want to check our Information Brokering thread on the Main board. You can ask there, someone will bound to answer you someday.

There are services for this on both the clearnet and the deepweb.