multi table / multi field search

[Lorenzo Parodi]

Our site, a non profit public utility one, needs help to develop a search function as follows.
We have a main table containing the pages text within a text field. We have some other tables (6 in all) containing lists of data used to dinamically publish certain additional information within pages.
We have already a fulltextsearch function working on the main table fields. It works very well and allows to scroll results in pages of 10 each. We nos need to develop a function able to make the same (including allowing a scroll), but to search at the same time withing some fields of all the tables containing information (lets say the mains one and the other 6 with data). We know how to make a fulltext search with different fields of one table, but nos how to do the same with different fields from different tables.
Any idea about how to do this ??