Smart Points

I have been lifetime for over 20 years, dropped out due to illness in family for 5 years, and gained back 15 pounds and am back.. I went to first meeting Saturday, and can't for the life of me figure out the smart points .. I was given Meet Your Plan,Eat Better and pocket guide.. If a food is not in pocket guide, I can't figure out how to get the smart points for that one item.. I have an old slide ruler from another program, but does not work with this program.

Do I need to buy the calculator WW sells, or is there a method I could use to figure out a food value..Thanks in advance

Smart Points