One of my favorite subjects.
Definitely the dogfoodanalysis site is great. But...to lessen the confusion I'd get a list of foods you are interested in & search for them because browsing can be very overwhelming. To get a good quality food you will have to find a dog/pet specialty store. Petco/Petsmart & other chain stores generally won't carry the good stuff. However, I believe those 2 places mentioned above do sell Wellness brand. I've personally never fed Wellness but it is a decent food & I know lots of people have fed their pups that with great success.
I have fed my Chi's both Solid Golds Just a Wee Bit & EVO. Both of those foods are all life stage foods which means you can feed them from pup to senior (as long as they do well on it of course). We just started feeding raw so we don't do kibble anymore...but my pups did well on both - but better on the EVO....which is a grainless food.
Other great quality foods are Orijen, Canidae, Innova, EVO (made by Innova), Solid Gold, etc. There are many more but that should get you started. Good luck & kudos to you for doing your homework prior to getting your pup!
**I just want to add that the most important thing to stay away from is corn. It is the most common ingredient that most grocery store brand dog foods are made from yet it is the #1 leading cause for allergies! On top of that, most grocery store brands are loaded with fillers, dyes & other things potentially harmful to your pup. (Most) Vets are even ill educated on pet nutrition - which is why they sell Science Diet & other foods I wouldn't touch with a 10 foot poll. LOL I can't tell you how pleased I am to see someone wanting to learn before running into troubles with a certain food.
Makes me jealous...I was one of the new pet owners who was led into the whole fancy commercial/bag/labeling/etc when first owning dogs. Thank goodness I found some great Chi forums and a great pet specialty store just after getting my first Chi. It was the most important thing I've learned from the net!