Generating a .nuspec file based on your project is not supported by NuGet.exe but you could write one. I do not know of anything that does this. However did you look at using the nuget pack command line?
nuget pack YourProject.csproj
This will generate your NuGet package file (.nupkg) and automatically add any dependencies for NuGet packages your project references.
You can include extra metadata in your .nuspec or just use the metadata in your compiled project binary.