Lion hides your Library folder. You can get to it via the Finder Go menu, Go To Folder, and
entering ~/Library or ~/Library/Preferences depending on where you want to go.
As for the dock thing, I realize you have a new system, but have you installed any third party additions at this point? Or is this still a “pristine”, as-shipped version of Lion?
The plist you may want to remove is,
i.e., that plist in your home directory Preferences. Log out and back in after you remove that plist.