I'd say social media. Gamers will be on Twitter and facebook. Target gaming twitter accounts and gaming groups on Facebook.
joined social media group and promote your link. spend some money to advertise in google ads,and join the popular forum to promote
If your game is awesome: exciting new graphics, engaging gameplay, wicked soundtrack etc... then it might be worth finding the influencers in the gamers world, its very personality-driven sector. Think Games Journalists/Bloggers/Social media gamer celebrities, and particularly for gamers... youtubers. They have large following of likeminded people who also are most likely to care about your game and they intern are most likely use your awesome game and spread the word. Send them an early release to try for themselves. VG247, PC Gamer, Videogamer, Kotaku, yogscast.wikia.com are a few sites that come to mind. Also Google ;-)
There are two good ways to follow in my suggestion box. First and most importantly, make the game very interesting and user friendly. Cause if people don't like what they are playing right at the first time, then your hopes will not look at you back. And the second way is using the social media. Most of the gamer hang out in Facebook, Twitter etc, so it would be a good idea to post some advertise of your game in social media sites.
A few ideas... *Find youtube videos in the gaming niche *Facebook groups *Twitter hashtags / any kind of social media *Join a few gaming forums and start posting Good luck! Marc
Create profiles on as many gaming forums that you can and drop a link to your site on your signature. Get active and traffic will come to it.
I only do "Paid Traffic". Start small and TEST, TEST, TEST. I start small with $5.00 per day and check your ad in 24 hours. Tweak it a bit to see what works. I typically spend about $200.00 to get the right add running then scale up like made. In less than a week you can have a profitable add and start making money. You will quickly turn your $200 spent in to $400 ROI and keep investing to scale up. For me social media, u nless you are placing Facebook ads, is a waste of time. Free ads cost you money in time.