2011 Buick Regal Shifter Knob Replacement 

You can find a new shifter in eBay or Amazon.
I used this: smile.amazon.c...
My only complaint is it's a bit closer to brown rather than black.
As far as getting the old knob off, I had to use a bit of force and break the plastic chrome piece. Don't be scared, just do it because I have zero clue how to get it off any other way. You're most likely going to be throwing the old part out.