How can I physically remove the internal memory device from my Samsung Galaxy S2?
This may not be as easy as you think. The eMMC is connected to the board with a Ball Grid Array (BGA) connection, which is pretty difficult to reconnect once removed.

You can see photos of the chip and more discussion on the topic on this XDA post.

As for where the chip is, you might be able to find it on some teardowns, but my eyes didn't catch it in iFixIts photos.