We have an 11 week old brown lab puppy, and we've used the method that bella outlined - whipping her outdoors if we caught her starting to wee, and praising/rewarding her when she did wee or poo outdoors. We're also using the 'be quick' phrase, and hopefully she will learn to do her wees and poos on command with that phrase.
We are lucky that the garden is totally puppy proof, so we have been leaving the back door open, and this week she's been taking herself outside to do her business, with only the occasional accident inside (though I did walk into the office to go on mumsnet to find a HUGE poo on the floor!!
She's been out for her first proper walk today - until now she's had little walks round the neighbourhood, but now she's had her jabs, we were able to take her out somewhere where there would be other dogs for her to meet, and she's paddled, met swans, played with other dogs, flirted with everyone she met and had a walk, so I am assuming that tonight's accident is because she's tired.
Yesterday, after dh and the dses had gone out for the day very early, having fed her and given her a run in the garden, then put her back in the puppy cage so I could have a bit more sleep, I was woken up some 2 hours later by the sound of her chasing the cat's food bowl round the landing. Ds3 had left the top of the puppy cage undone and she'd opened it, climbed out and been entertaining herself downstairs, then come up in search of a snack and me. She hadn't trashed anything, or eaten the newspaper, and she'd even been out through the catflap to go for a poo on the lawn.
Mind you, at the rate she's going, she's not going to be able to use the catflap for much longer - I have visions of finding her stuck half in and half out.
Threeandcounting - I will take a look at that Perfect Puppy book - we've got a book on labradors, which is very informative about all sorts of things, but obviously can't cover training in any great detail, so I do want to get a good puppy training book, as well as going to the puppy classes.
AGal - it sounds like you are doing fine, and your puppy is too - and I hope she gives you as much pleasure as ours is giving us. Oh - and I'm a novice dog owner too (dh grew up with dogs as pets, but I've always been a cat person) so maybe we can talk eachother through the experience?