You could just add it in manually by adjusting it in the functions file first, and then adjusting them in your style.css file. That’s how most dev’s do it, but I can understand if you don’t want to touch the code.
Here is a quick tutorial – http://my.studiopress.com/tutorials/load-google-fonts/ …there are plenty more if you need, just do a Google search.
You can also go to the Google Web Fonts site so you can not only get the import code, but you can also get the proper CSS code you’ll need to add to your style.css file.
If the plugin you’re using isn’t working, then I’d just add it in manually. You do have to add the code in manually, but you don’t need to know code in order to do it. It’s simply copy/paste…..Actually it’s copy/REPLACE I can help if you need assistance.
EDIT: I thought you were using a plugin that is specifically for Google Fonts, my mistake. You should still be able to use that plugin to add customizations. Do you have a link to your site? That would help me figure out what’s missing to get it working.
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