we don't find theme editor in our blog we are using free(default) template of word press can some one tell us where is it located ?
Log in to the admin panel, then go to Appearance=>Editor. There you can edit files of the theme if you have permission to do it.
you can do like Mr. s_ruben said. then you have to find out the </footer> html code.. I think we have to put the Google analytic code before that code...
under appearance > theme editor. for adding new theme > appearance > theme > add new > activate > then u can edit theme file in editor.