Magento Categories & Products CSV Import help

General information for the website: NA
Description of requirements/features: I'm looking to use Magento for multi site project, I can install and setup the correct currency and everything else fine, the issue is the data source that I've been given for the categories & products have been dumped from dynamics nav in to CSV files and a lot of the data is repeated in each CSV file, I'm looking for someone to help me get the files in some sort of order to be able to import them as Categories, Sub categories, products and so on, there is around 5 CSV files but I'm sure only 1 or 2 of them will be needed.
Specific technologies required: Magento, CSV, Import / Export
Extra notes: Ideally I just need someone with Magento Experience to look at the files and give some advice and possibly help me get them into some order to import the data into Magento, so I have a working import CSV template based on the current CSV data.