where can i burn cds free of charge
Are you asking what program to use?
Most computers that have a CD burner will come already loaded with a program to burn CDs. Popular ones that are loaded are Roxio CD Creater or Windows Media Player.
download.com also has some free programs that you can use, but they're not as good.
Down load and use the free version you can download at this site. http://www.deepburner.com/