It all looks pretty normalised already. The only odd thing is that none of the tables appear to be related in any way. Shouldn't Products be related to Manufacturers, Complaints to Customers? i.e. by foreign key columns?
Well what I was given was the UNF for the data. There maybe one or two errors when I copied it down. But could anybody put the information there into 1NF, 2NF and 3NF? Correct one or two things if you have to.