What are the best tools for preparing and styling a table in Wordpress easily?
I want to prepare and publish the tables in any page or post. So I think it might be easier if they can be prepared with an easy to use shortcode.
WP-Table Reloaded is a great plugin which allows you to create tables and use their shortcodes in your post. Bear in mind, however, that not all themes are "table-friendly".
Alternatively, you can try Dean's FCKeditor Plugin For WordPress, which appears to have an "Insert Table" function to keep you from messing around with HTML.
And the best option, in my opinion, is to learn a couple of HTML tags to wrap your data into tables, and learn a couple of CSS styling rules for those tables.
TinyMCE Advanced gives you the option to add table-related buttons to the WYSIWYG area. Not extremely powerful, but it gets the job done.