Names not handles!

Hi all I like to call people by their name, not the user name. Is there a easy way to find out what is their first name! I feel funny asking all the time and my memory is not the best so I forget, I am going to start writing them down so I have a reference! But new people I search their Spark Page and no names, I hate using the username, it seems impersonal, but maybe some people don't feel comfortable with everyone knowing their name, even if it is just a first name.. Blessings, Deb