where can i find a site with the latest demo's

im sick of getting games that suck, tbh and just wounderd where i can find the latest demo's so i can try before i buy anyone got any tips or info on where to find them and please dont say google as i no all about it and its my friend lol but would like to get one site that gets them all =0) if thats possible oh and i no gamespot does alot but speeds are crappy lol