http://www.gbatemp.net, http://www.dcemu.co.uk, or http://www.qj.net/. Just popular all rounder gaming site forums are good
Use a program called hypercam2 where you can record things on the desktop and stuff and then you upload the video on youtube and then you will have a lot of guys wanting your game or whatever it is. hypercam2 is a free program you can just search for it on google if you didn't know it exists already.
It depends on what kind of game, really. For game maker/ RPG maker/ homebrew RPG you're better off posting on general gaming sites/forums. For flash games I'd try a site like Newgrounds or other game portals.
I just realized that would take some time to do, if anyone would like to help me with some of that stuff (seeing as how I'm busy updating the game etc etc.) it'd be extremely appreciated ^_^