Detect tables in a spreadsheet?

Hi all,

I'm looking for way to detect a table in the spreadsheet. I know there's a way to get it through the SDK, but it only works for those tables which were inserted and defined as a table (TableDefinitionParts? or getTables() in POI). However, it doesnt work for those table which were constructed manually, by entering column names, headers, changing styles, entering data etc

any ideas how to achieve this? any algorithms/sample code/SDK you can lead me to? 

thanks

Lior