there is a really helpful site when it comes to researching foods. The link is
www.dogfoodanalysis.com I read through all of the most common brands mentioned on here and I decided to go with Innova because it's holistic (meaning only whole parts no by-products) and reading the ingredients list I would want to eat it. There are other great foods but I thought I'd share what I chose seeing as how I'm a first time dog/yorkie owner also. My Sophie is only 14 weeks. She is great!
ohh and by the way if you choose to read about the food on that site, skip the 6 star foods as they are too high in protein for yorkies. Hope this can help you with your decision!