I wanted to welcome you ASAP to our little family here in the States. It's high time we shook hands in person and not just across the sea. I'm pleased as punch about getting to know you all, and I for one will do my level best to sell you on America.

Question

are you a new instructor. For business communications

I assume you want this critiqued.

ASAP is not a universally known term. "pleased as punch"...What foreign person would have any idea what it means?
see http://www.word-detective.com/052699.html#pleasedaspunch

Shaking hands is not a good practice unless you know the customs of the foreigners.
Finally, "sell you on America". ARRRRRGGGGG. You had best stick to your company.

You wrote, "I wanted to welcome you ASAP to our little family here in the States. It's high time we shook hands in person and not just across the sea. I'm pleased as punch about getting to know you all, and I for one will do my level best to sell you on America."

Better, might be this:
Welcome to our company's headquarters in the United States. While you and I have spoken over the telephone and in e-mail, I will be very happy to finally meet you get to know you in person. Again, welcome!

... or something like that ... without all the slang and hideous phrasing!

=)