I'd start with some videos on youtube.
This was one of the first videos I ever watched on CT, and it's great for understanding how you can shape behaviours swiftly and without stress using a clicker: (It's a mule, but don't let this put you off!).
That video is from Karen Pryor's organisation - she's fantastic so the rest of those videos (esp. the "Tucker Nail Trim") are all worth watching. Her book 'Don't Shoot the Dog!' is also an excellent resource.
It sounds like a clicker would be good for you both. He needs to follow commands not because you have a treat with you, but because he gets used to being rewarded for actions, and this becomes 'proofed' in different situations.
First you will need to introduce the clicker - get a bag of very tiny tasty treats (I use sausages or liver cake cut up vvvvv small - they're smelly and my dog will work for them, whereas most other treats she'd not be fussed! Use the treat your dog will sell his soul for in the early stages - it has to be a valuable reward for him) and your clicker. Use your dogs name and when he looks at you, click and throw him a treat. you want to get him used to the fact that the 'click' sound means that a reward is on its way! Try to click AS SOON as he looks at you, so there's no delay.
Keep sessions short (no more than 5 minutes), and end on a high before he gets bored!
If you can, try to have a one-to-one session with a good clicker trainer, as that will do wonders for your timing - this can be tricky to get the hang of to start with.
Good luck!
Another thought - my dog doesn't like to sit at the kerb (I think 'the princess' gets a cold bum, despite her fluffiness!!), and I don't make her. Lots of dogs aren't keen - esp whippets and greys I believe? Ours has been taught the command 'wait', and that's fine for me, as it achieves what I want and isn't something unpleasant for her. Might be worth choosing your battles?