I’d previously used a stock theme for this blog, but the current one is something I designed specially for it. The theme is called ‘respond’. It’s available for download at: http://www.a2wd.com/dl/respond.zip
If you’re interested in using it on your site, go to appearance->themes->add new->upload and upload the zipfile directly.
If you’re on a localhost and the ftp upload screen is proving problematic, just unzip the contents to your wordpress installation directory under /wp-content/themes/