Those are just few of the websites that i knew of where you can get your new templates. Before editing your template, you may want to save a copy of your present template by simply clicking the Download Full Templates under the Backup / Restore Template, just in case something goes wrong you can still restore your old template. Another thing that you have to make sure is that you need to saved all those widgets/codes that you may want to remain in your blog, save it to either notepad or MS word because if you wont the tendency is you will end up loosing all of them. After pasting the new template (html/code) you can preview it so you can see the whole picture and change it if you don’t like until you get satisfied then click save.