The property GeckoElement.Attributes allows access to an elements attributes.
So for example (this is untested and uncompiled code):
public string GetElementAttributes(GeckoElement element)
{
var result = new StringBuilder();
foreach(var a in element.Attributes)
{
result.Append(String.Format(" {0} = '{1}' ", a.NodeName, a.NodeValue));
}
return result.ToString();
}