I have been feeding backyard birds at my house ever since I was a child and continue to do so as an adult. I actually keep an encyclopedia of all birds in my region and check off each species as I come across it, noting where and when the bird was spotted.
If for some reason I can't identify the bird in the picture that you send, I will work with you continuously until identification is made. Sending me a clip of the bird's song and detailing your observations of the bird will come in handy at this point. I will not break communication with you until the bird is properly identified, but in most cases just sending me a good, clear picture is enough.