I'll second Ineti: it seems that your best bet is to go straight to the source and look at their available job listings. Often you will have to click around a bit, usually going to the company's website, finding their "About Us" then "Careers" page. Otherwise, their sites are usually tailored towards customers.
If you mean to write about games, I would try and find submission guidelines or career pages for gaming oriented websites and magazines.
Do you have any game companies you particularly admire or enjoy the games of? If I ever wanted a job in the video game business, I can think of at least three I would love working for.