I am trying to figure out a type of bird around my house. medium sized with long tail and beautiful songs?

The bird is medium and appears to be mostly gray but when it flies it has white strips on its tail and wings. It spends most of the day going from my tv antenna to the lightning rod on my barn to a the top of my shrubs and my small trees and is always singing. It seems to have so many different songs and they are all beautiful. It just sings to me all day. I just love that bird, but I am having trouble figuring out what it is. I will keep looking but maybe you can help or know of a web site that would make it easier. I live in the country but more fields than woods. The closest woods it about 300 yards away. I have lots and lots of flowers and some small trees like plum and cherry. After I figure out what kind of bird it is, then I want to know how to keep it around. Thank you very much..