Apple Logic Pro /LogicExpress Discussion

As I've mentioned before on this list, I use Logic as a hobbyist. So as you
might suspect, there is a lot I don't know about Logic. There is also a lot
I don't know about the Audio aspects of sequencers because, up to this
point, all of my music has been done with midi instruments. The only audio
I've recorded was vocals.

So... Here is my question. It is impossible to simulate (at least for me)
guitar strumming using my keyboard. Is this were Audio loops come in handy?
Do you search through a library of guitar samples looking for one that is
strummed the way you want it to be. If not, does anyone have suggestions for
creating realistic strumming on a MIDI instrument?

Kamm