CSV split, and filtering email addresses by location etc

I'm new to freelancer.com as well and didnt know that you could offer upa project for far less. Basically there are 5 csv files ( of 100 - 500mb in size) which I want divided into xls and/or csv files that are in the 10 - 20,000 line type ( i think Excel cant open anything bigger than 50-60k). These are databases of Chinese businesses. i'd like the split of all the lists into manageable 20K type chunks/files, AND, extract data based on their chinese city location. To make it simple, I am only keen on getting manageable email lists ( as a subset) of Shanghai, Beijing, Tianjin, Shenzhen, Guangdong. So, the final product should be: 1) A specific numbers of XLS and CSV files of no more than 10-20K email addresses each from the 5 zip files you find on that URL 2) Subsets of the entire database of email addresses belonging to companies that are: 1) based in these 5 cities 2) in the Managing Director, Senior VP, or HR Manager/Director level 3) are companies employing more than 50 persons My intention - to send marketing material by email (only) to companies that are based in these 5 cities, and that they are >50 staff in size