Since you know them personally, ask them for their Spark names, then search for them.
BUT, you have to spell the name right AND they have to have made their Spark page public for you to find them!
Another option is to give them your info and they can find you first!
“We cannot change the cards we are dealt, just how we play the hand.”
~ Randy Pausch
"There's a difference between interest and commitment. When you're interested in doing something, you do it only when circumstance permit. When you're committed to something, you accept no excuses, only results."
~ Art Turock
"We have a saying in Tibet: If a problem can be solved, there is no use worrying about it. If it can't be solved, worrying will do no good."
~ 7 Years in Tibet