Is there a jQuery plugin for resizing table columns that works with tablesorter?
It looks like Flexigrid has everything you may want.
It looks like jquery.kiketable.colsizable would work for what you need.
Another one that looks good is Ingrid, the jQuery Datagrid. It has more features and will sort your columns without the use of tablesorter.
You should try the colResizable plugin. It allows to resize columns manually, and it is tiny in size (2.8 KB) and does not require any other libraries or stylesheets.
A very easy plugin for adding resizable columns is SimpleResizableTable.js.
It is possible to use the jQuery UI Resizable plugin to resize columns. The plugin can not directly resize TH elements, but even better COLGROUP > COL elements which makes the browser rendering very fast and enables proper HTML.
Some more evaluation, a live demo and complete code can be found in the blog post Resizable Table Columns with jQuery UI.
If you don't find a plugin for tablesorter, the jQuery Grid Plugin (still in alpha) does resize columns.