If people used google there would be a lot more questions answered and less troubleshooting threads. You can download steam at http://store.steampowered.com/
Anyways steam can more than handle the small Total War community. There nearly isn't as many total war players as lets say HL2. Downloading with steam is much faster then most file sharing sites because there is no bandwidth cap. So you can download at the fastest you internet connection allows. So even though it is only on steam it will still be faster to download through steam then file shack, file front, gamers hell or whatever because of no bandwidth caps.
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