Oh thats a totaly shame - and so difficult because many small dog owners really dont think their dogs bad manners are a problem - there are some owners here who let their little dogs hang off bigger dogs - and do nothing cos 'the other dog needs to tell them off'
If you are meaning using the 'look at that' rather than the Premack principle then how I taught it

Keep Kismit (onlead) at a distance away where she can see and is aware of the little dog - but well before she is stressed
Then when she looks in the direction of the dog click (or I use a clicker word 'YES' because I dont have enough hands) - hopefully she will look back to you for her treat, but give her a treat anyway - dont wait for long periods of looking at the wee dog - she is being rewarded for glancing at the dog
If she is stairing and cant look back to you then you are too close to the small dog - take a few steps back
Repeate a few times then walk totaly away from the dog - so she learns that looking at small dogs then back to you is a trick - but she dosent have to interact with them - so there is no fear of something nasty going to happen
Do this every day you can (difficult to set up dogs I know) and you will see she is 'getting it' if you delay your 'YES' and she looks back at the dog and to you - or even starts to offer other tricks - basically saying 'didnt you SEE me looking at that wee dog??' then looking at the dog - and back to you becomes part of a game and she will get calmer

It might also be an idea to teach her a solid 'get behind me' position or something so if a wee dog is intent on charging up you can have her in a position where she is safe and you can deal with the other dog
Of course it will take time before she is calm enough to listen - afraid your gonna be scanning the horizon for wee dogs for a while

Hope you find a good behaviourist, its such a shame you are having to pick up the peices from someone elses badly behaived dog. and its horrible people saying you have an agressive dog, I have had people yell at me to get Mia put to sleep and that if they see her they will put her in a skip

I love people!

I like that Ben - I'm going to try it with Bryan. Do you think that Kismet needs to be made 'operant' first? It's taken me a little while to get Tilly to realise she has to work for the treat and use her own brain to figure it out

Bryan on the other hand is a little huckster and tries everything just to get a click

you are so right, i was thinking i remembered kismet was clicker trained which would make her quicker to figure out that her behaviours were making the treats happen
it worked so well with mia because she is such a manipulative wee maddam trying to figure out how to get you to do what she wants
would be much slower on ben, i didnt clicker him properly to start with and unless i tell him he is on free time he just stairs at me waiting intently for me to tell him what to do, looking at something else would need to be something i free shaped on something inanimate before taking it on the road

Bryan is much more manipulative the Tilly. I keep meaning to start a blog to track their progress with the free shaping....I might go and do it now

cool, cant wait to read it
free shaping is so cool, the things people can train with it is just mind boggling

Kismet is not clicker trained, but I have always used the 'free shaping' method of training with her... She is too intelligent and stroppy to be trained any other way. She likes to do whatever she wants so I let her throw herself at the problem until she figures it out then reward and start again...

I can't find anywhere to walk at the moment where there are a few small dogs to work with. Either there are no dogs, or we would have to go back to the scene of the attack and be bombarded with hundreds of angry little dogs.

Still we are working on it. I have started to cross the road or change direction whenever we see a little dog at the moment and try to walk a few paces behind them for a few paces. Rewarding Kismet if she stays calm and keeps to heel and stopping if she makes any aggressive moves. I have become a weird small dog stalker!

It's working, slowly but surely. She is starting to pull towards small dog walkers, but not in a growly aggressive way more positive and keen to show she can walk behind them and get a treat.

I'm taking it as a positive and once we get to the point where she can actually walk past and cross paths with the other dog, not just trot behind them. Then we will try going back to the big field.

I know this is serious but I just got a mental image which made me laugh

Sounds like it's going well though Magpye. Tilly played with a new dog today (a GSD/Rottie cross) and I was so proud of her. She barked a little bit, but it wasn't aggressive and the other dog didn't mind.

Sounds like you are both making progress

Sounds like Kismet is smart - only think I would mibby think about teaching her something other than pulling towards small dogs - although it is great that her frame of mind is changing towards small dogs if she is seeking them out to show you how good she is she might still meet up with a bad mannered dog and you will be back to square one again - might be an idea to let her rewarding position to be coming to your side when a wee dog is there or something like that??