You can get cheats for this game by simply Google'ing them. And I wasn't a big fan of GTA 4. To me it was very overrated. The story mode in that game wasn't very long either, at least not as long as the other games. They also took out the offline multiplayer, so that was another bad thing. I didn't like the online multiplayer too much either, it was basically just people sitting around with snipers waiting for others to run out into the open.
GTA 4 was ruined for me because of Saint's Row 2, a game that made me expect so much more awesome from GTA IV that I just didn't get. Saint's Row 2 and its recent "The Third" sequel are far superior games, leaving that annoying cousin of mine and his bowling alley fetish far, FAR, behind me in the dust.
gta went down the road whit gta4 because they went realistic. gta was a great game whit it's surrealism. (bunny-hop 20 feed whit a bicyle) saints row is the new gta