Most of the "best" Steampunk that I've encountered has popped up in either Comics or Novels.
In terms of Novels I can recommend...
The Court of The Air by Stephen Hunt
Perdido Street Station, The Scar or The Iron Council by China Meiville
Sun of Suns by Karl Schroder
The Diamond Age by Neal Stephenson (Sorta Steampunk, Sorta Cyberpunk, Lotsa WTF)
The Anubis Gates by Tim Powers
In terms of Comics I'd go for...
The League of Extraordinary Gentlemen Vol. 1 by Alan Moore and Kevin O'Neil
Nausicaa of the Valley of the Wind by Hayao Miyazaki
Steampunk by Joe Kelley and Chris Bachello
Sebastian O by Grant Morrisson
For Videogames...
Final Fantasy 6
Arcanum: Of Steamworks and Magic Obscura
Rise of Legends
Skies of Arcadia
All of these works I would say "get Steampunk right" and have a lot of fun with the wacky, impossible technology.