Need help redesigning my database...!

Hi,
I have this database now:
the database holds products and the stores that sells them...
colums are: id (auto,1ry) name, price, category, category id, store, store id

Now, I think.. to make new table for categories, and also add subcategories... and make a new table for stores...
Is this a good thing to do?
I am only bothered with employees who add new category names wrong or store names..
making a table for the categories and stores would make 1 row for each store..
So, what do you guys think? or you have a total new way?