From my understanding, when it is at port, it is being prepped for shipping and waiting on a boat.
When you call the 1-800-831-1117 number for BMW NA, say vehicle production status, provide your partial VIN(last 7 numbers/letters of VIN) or your production order number, then tell them it's an order number or a VIN.
When they tell you it is in transit, check this website
http://www.2wglobal.com/www/WEP/index.jsp.
Select customer center and click track and trace.
Next enter your entire VIN number (you can get it from your dealer) into the Cargo ID box, then click track. If you have a problem, make sure you entered it in the correct box. It's the box to the right of the words "cargo ID"
This should pull up the name of the ship you are on, the port your car is destined for, and the approximate date it will arrive in port. If you click on the voyage number link, it will pull up the destinations for your ship and the approximate dates in a seperate window.
You can then track your ship (if in range of shore beacons) with this website
http://www.marinetraffic.com/ais/. If it is in range, you should be able to find it by typing in the ship name.
If it is not in range of shore, you can use this website
http://www.sailwx.info/shiptrack/index.html Enter in your ships name (or the call sign if the name does not work) and it will give the last reported position. The call sign is available on the Wallenius Wilhelmsen Logistics website (first link I pointed to above). Sometimes the ship will not report very often, or at all during the transatlantic crossing, so don't worry if your ship does not update.
It's also possible that your ship will not be on a W&W ship. If that is the case, there are a few other lines, but I would try this site first as they seem to be the primary carrier of BMW cars to North America.
If you have any questions, please don't hesitate to ask. I am awaiting my own car just as much as you are awaiting yours. Helping others as I was helped is a good feeling...plus it keeps the itch to track my car down and that makes my wife happy.