launch GW without Steam?

I currently play GW through Steam, which means I have to log into Steam first before it launches GW. I noticed that I can close Steam (by killing its process), and still play GW, and keep any changes I made in the game (because it's all stored on ArenaNet's servers, not Steam's).

So is there a way to launch GW without going through Steam?

Certainly. Just locate gw.exe with the Explorer or through other means and start it directly or create a shortcut to gw.exe on the desktop.

Locate gw,exe using Windows Explorer. I don't know if Steam puts it anywhere special, but it's normally in C:\Program Files\Guild Wars. If it's not there, search for it.
When you locate it, right-click on gw.exe and select Send To > Desktop (Create shortcut)
That will put an shortcut for GW on your desktop. As a bonus, this shortcut will also have a regular "Target" line where you can add things like -image when/if needed.