We've found this table helpful, especially since DD had feeding problems in the recent past:
kellymom.com :: Calorie and fat content of common baby & toddler foods
I'm sure there are other sources on the web, but I liked this table's breakdown into calories and fat content per ounce. It's made us emphasize some foods like avocado (which we'll be trying this weekend), and de-emphasize others (carrots) unless mixed with cereal. DD will still get all the foods, though.