it honestly depends. The standard place is mediavps\data. If it's for a mod, it goes in (modfolder)\data. If you want it to show up when you don't have the mediavps selected, it goes in freespace2\data (for example, multiplayer missions).
You can find an explanation of where everything goes
here. Just use the folder you selected above instead of freespace2\ .
Just to quickly answer the ones in your post:
.ibx isn't needed (It's automatically generated), but you can use it by putting it in mediavps\data\cache.
.tbm goes in mediavps\data\tables
.pcx, .dds, and other images depend on what they are. normally, they'll go in either effects or maps, depending on what they're being used for.
EDIT: And being rude isn't the best way to get people to help you.