The title of your post asks for the best dog food. Here is a link to dog food ratings:
Dog Food Reviews - Dry Dog Foods - Powered by ReviewPost
You can start off with the higher rated foods. From there, you have to make sure that your puppy likes it, and that it works for his little tummy!
As others have suggested, sometimes you can get sample size bags from the healthy dog food/pet supply stores. The last time I went to mine, there was a rep from Nature's Variety. This is the brand I have been using (switching from Eukanuba - recommended by my breeder - after reading around this site). I got some coupons for the food (yea!), and also for their raw food, which I had been thinking of trying.
You might also try the manufacturers' websites for free samples or coupons.
