Scoopers - 3 different sizes. A 1 Tblsp for truffles, a 2 Tblsp for cookies and an ice cream scoop one for cupcakes.
A set of baking sheets. My Uncle Joe bought me some from Bed Bath & Beyond for Christmas one year and I love them! Nothing fancy...they do the trick.
AND...Silpat mat and/or parchment paper. This is absolutely essential for making sure your cookies, loafs and brownies, bark, bars, krispie treats, toffee, etc, etc don't stick! You don't even need cooking spray when using these things. Parchment paper is good to use for cakes.
Seive or Sifter. When a recipe calls for dry ingredients...ALWAYS sift. I use a strainer like the one below to sift. I have a Sieve but, man, that thing makes your hand tired.
Disposable Pastry bags & tips. I find them really, really useful- you can even use them to pipe batter into tins, but using them for frosting is what I use them for most.
Mixer & Measuring Cups/Spoons. These should have been first on my list but most people have 'em. Buy good measuring cups & spoons - not ones where the paint scrubs off. I have the all-clad and hear them! I have a kitchen-aid stand up mixer but also have one of these and use it for frosting or when making icing.