last year of business in Canada?

[bordercrossing]

Hi, I'm a Canadian citizen moving to the US in late January 09 on a K-1 fiance visa, so my move is permanent. I have two questions.

I am a freelance writer who files my Canadian taxes accordingly, with self-employment income. From past tax years, I know there is the question "Is this your last year conducting business?" on the tax forms. What I am wondering, is it best for me to consider 2008 my last self-employment year in Canada, or wait until I file my 2009 exit return?

I don't anticipate any income or expenses for January, as I am only here for a few weeks before making the move. But is it better to "end" my business activities at the same time I complete my final 2009 exit return? Or should I just do that now, for my 2008 return? Any pros or cons to doing it one way over the other, if optional?

Also, my last question - I have read up on self-employment taxing in the US, previewed the tax forms, etc. But I also seem to run into information about requiring a TIN if you run your own business. My question is, since I am self-employed doing freelance work from home (this will continue once I move to the US, but from US sources I predict), and have no employees and a very modest income, do I purely file with self-employment tax paperwork, or do I actually register myself as a business in the US, or specifically in Michigan where I will live? Or is that only if you run a business employing others etc?

Your response is appreciated. Thank you.

[nelsona]

Your SSN (which you will get soon after you move to US) will serve as your tax ID.