[Theme: Twenty-Twelve] Add custom font style, then style w/ Google Fonts plugin

Hello,
I am new to CSS. I am using the Twenty-Twelve theme. I would like to add a custom font style so that I can style the fonts using a Google Web Font. I am using the Google fonts plugin to do this. Eventually I would like to be able to style the font in a post like:

<special>Google Web Font</special> rest of text in normal font.

1) What do I add to the Twenty-Twelve stylesheet to create this?
2) Will the “special” style auto-populate in the Google fonts plugin? If not, how do I designate the font style using the plugin?
3) How do I designate the style in a blog post?

What I have already tried: Simply adding a new CSS style to the Google Fonts plugin and then styling in a blog post per above. This only worked in Firefox, not IE. I would like a cross-browser solution if possible.

Thank you for any help.