I just installed Flatabulous (a theme) on my computer that runs Xubuntu.
This happened on my desktop:
It seems that the icon text is left-aligned.
I tried looking around /usr/share/themes/Flatabulous/gtk-2.0/gtkrc
like others have suggested, but I couldn't find any styles that concerned the icon alignment.
From the xfce docs, it says:
Hidden Xfconf Options
There are a couple of hidden xfconf settings that cannot be set by the xfdesktop-settings application. The channel name that xfdesktop uses is 'xfce4-desktop'. For more information see the Xfconf Documentation.
…
/desktop-icons/center-text
Boolean, default is TRUE.
This value controls whether the text for all the desktop icons label are centered.
I believe this is the correct setting, but I couldn't find it anywhere. It says it should be in xfdesktop-settings
(the "Desktop" application), but it's not there. Any tips?