This is an American expression which can be used in a number of ways:
1 To obtain an item, by purchase, borrowing or other means;
2 To initiate contact or
communicate with a person or persons or an organisation;
3 To
understand or
appreciate an idea, concept or theory;
The British use the expression get hold of in a similar way.
1 “Can you get ahold of any 2 inch 10 brass screws?”
2 “
That cunt Malcolm’s gone off
somewhere, I can’t get ahold of him.”
3 “His ideas are so abstruse they’re
difficult to get ahold of.”