for a wishlist, you need to use SecurityAssist to add user log in, and DataAssist to store the items into a wishlist table.
when the user logs in, a session variable is created with their ID. you will need to create a new wishlist table that is used to relate the wishlist products with the users that added them.
the structure is fairly simply:
wishlistID -Primary Key
wishlistProdID - foreign key relation to productID in products table
wishlistUserID - foregn key relation to UserID in users table.
when the wishlist button is pressed, the productID and UserID are stored in the wishlist table.
to display the wishlist, create a join query on the products and wishlist table:
INNER JOIN wishlist
ON products.productID = wishlist.wishlistProdID
WHERE wishlist.wishlistUserID = $_SESSION['UserID']
you will need to substitute the column names in your database and the session variable name as well, this is just an example of how the query will work.
the wishlist is really just another product catalog page, the only difference is that the products are related to the user who added them to the wishlist.