why doing it in the human way when you can teach your dog much faster in the dog way? I have two big dogs myself, one of them is a 6-month old puppy and I can tell you there's a big difference between having your dog sit down and come to you. the first one is a command, the second one lagely depends on your dog - as long as it has a choice. At your puppy's age, however, it should still more or less follow you and stay close to you. If it doesn't, then there's a problem. Not a training problem or obedience problem, but a pack problem, a relationship problem. That's what you need to work on, there's plenty of time for starting with commands.
Yes, my puppy has also been through the biting and nibbling phase. I'd say it'll partly pass and partly you need to show your puppy it's wrong to bite on people. A "no" is a good way, but it must be authoritative enough (but not yelling, calm but firm voice and show the emotions), however, as I really think it's much more efficient to talk to dogs in their own language, I press my puppy's mouth or growl at it when I want to show dissatisfaction. This is something their mother would do and they don't need to learn it as with human words...
And by the way, if you're interested in the natural dog's behavior and communication, here's a link to my favorite site
[url]http://psiskolafalco.web3.cz/index_en.htm[/url]
good luck with your puppy! :-)