well basically u first have to learn how to read notes and count beats..you have to make sure that u have control over your breating and use alot of breath to produce notes with a high quality...
if you are looking to buy books with the pop songs in, on the internet or in shops, look at some of the companies that do lots for all different instruments. i use a lot of take the lead and...
You can buy basic books and books with famous songs in them from online music stores. You can just play the songs for fun as long as you know the notes. www.musicroom.com(C) is a good site to buy...