Simple scenario needs to go from Unnormalized Data to 3NF - Review Please
Yes, it's in 1NF.

You can't side-step the often hard work of determining all the candidate keys by hanging a number off the end of the table and saying, "There. I've got a primary key."  One natural candidate key for this table is {Name, Bought from, Date bought}.  Consider using "Time bought" instead of "Date bought".

Your definition of 2NF is wrong. Instead of 


  Second Normal Form: A relation that is in First Normal Form and every
  non-primary-key attribute is fully functionally dependent on the
  primary key.


you need something more like this.

Second Normal Form: a relation that is in First Normal Form, and every non-prime attribute is fully functionally dependent on every candidate key.

The term non-prime attribute doesn't mean quite what non-primary-key attribute means.

Your definition of 3NF is wrong, and it's wrong for the same reasons as your definition for 2NF was wrong.

Instead of this


  Third Normal Form: A relation that is in First and Second Normal Form
  and in which no non-primary-key attribute is transitively dependent on
  the primary key.


you need something closer to this.

Third Normal Form: A relation that is in Second Normal Form and in which every non-prime attribute is nontransitively dependent on every candidate key. (There isn't a really good way to express all those negative in one sentence.)