ID:1239303
 
It took me a stupid amount of time to figure out how to add someone to my pager. I feel old now. I recommend putting an Add Friend button somewhere on the Friends tab.

Also, you might want to change Lookup to Search for all the tabs. I don't think "lookup" is actually a word and "search" is more or less the standard term for the function of that button.
It's strange, I figured it out instantly yet you're not the only one who's had trouble with it.

Although, I don't think any social networking sites nor Skype have the option to just type a name and add it to your friends list. You usually have to look someone up first (look-up is a good word for it) and then add from some kind of profile page.
I just wish the lookup function would search entire names, rather than just the beginning of names. ('tom' / '*tom*' could return 'Dantom' rather than just 'tom*' results)