I would like to import and export all categories, attributes and products, Magento will only let me imprt and export products. What should i do?
It won't do that out of the box.
There appears to be many plugins on connect.. but you're likely need seperate ones for attributes and categories..
I've not used either of these extensions - so cannot guanratee the quality of them; or whether they would work for your scenario.
iweb_p3mbo is right, Magento cannot do it out-of-the-box.
There is all-in-one solution - Store Manager for Magento that allows to export/import categories, attributes and attribute sets, products with related details.
There is fully-functional 14-day trial, so you can do the task without additional expenses.
You can download it on Magento Connect at -