The firefox extension TableTools (https://addons.mozilla.org/en-US/firefox/addon/2637) sorts, filters or copies any HTML table. Two filtering modes supported: select filtering (each column has one drop down menu allowing you to select a certain value); search filtering (each column has one search box allowing you to search for any value in the column using keyword(s) or javascript regular expression.)

Once the extension is installed, to get the table sorted according to a column, right-click on it, access the ‘Sort Table column.’ menu and select the appropriate option (or use the keyboard shortcut - Ctrl + Alt + click).

And to copy the data so that it can be processed further, right-click on the table, access the menu ‘Other Table Operations…’ and select the relevant option (or Ctrl+click+Q).