black oil sunflower seeds probably attract more birds than any other feed. you can use a tube feeder or a mesh wire feeder or even a hopper feeder. Suet is a great treat in winter but some birds eat it year around. you can use a suet cage and buy suet cakes or make your own suet mix. there are lots of old posts on here making suet. if you like doves and juncos and other ground feeders the seed mixes with cracked corn ot millet do good but they also attract blackbirds and starlings and cowbirds which lots of people don't want around. the summer song birds such as tanagers and orioles and grosbeaks like fruit or berrys or drink from necter feeders. or plants with berrys or blooms and blossoms. the woodpeckers i get here love nuts and suet and cracked corn and millet. robins and bluebirds like mealworms or grubs or earthworms the tits and chickadees and nuthatches like suet or hulled sunflowers or boss or nuts.

Thrilled for you!

How exciting that you have birds coming to the feeders. They are fun to watch. As DKlucious said, black oil sunflower seed (BOSS) will attract a wide variety of birds. The hulls are pretty messy unless you buy the hulled seed which is a lot more expensive. If you'd like to attract woodpeckers, they just love suet. During the colder months I buy the raw suet at the grocery store and put it in a small suet cage. Other birds nibble on the raw suet too, but the woodpeckers are quite partial to it.

I also make a home-made peanut butter suet mixture that lots of birds go crazy over, but to be honest, during the summer the only time I feed that is when the Bluebirds show up! They get special treatment. I've also planted many grasses, perennials, and shrubs that provide natural sources of food, and lots of hummer plants.