[development] Implementing without nodes

I'm trying to figure out how to implement several modules, that do not use nodes at all I need to set lots of forms, this forms are used to edit, insert or search my tables I'm having dificulty controling the data flow of my forms. What hooks I use? I try hook_form, but any code I set there isnt executed. Every site about hook_form, uses node! Can I do that without nodes? TIA Feijó