I know if you are a newbie blogger, just like me 4 months ago, You will have no problems with standard templates, which Blogger, Wordpress or Typepad offer. I got to say those standard templates are not quite interesting, they are not much of an attraction to the visitors.
If your template is looking fresh your visitors will return just like they come back for good content. I replaced my previous template for a newer one because I thought this template represent http://meangreen-meangreen.blogspot.com/ just like the mighty US dollar.
Anyway I found out that if you want to replace your template, then you have to get a beta Blogger template, incase you have a beta account. Otherwise when you revert to classic template you can only display one Adsense ad. This can be a big disadvantage if you get a lot of visitors
So, if you want to download some nice Blogger templates go to http://www.finalsense.com/ get it for free.