You could try Greenies treats.My dog loves em and they keep his teeth really clean plus his breath isnt as bad!!! alot of stores sell these and they are fairly cheap
We give my puppy cheerios and she loves them. Ice is also a good treat, as they love to chase it, especially on un-carpeted floors. Carrots are good as well...all of these were suggested by the vet for us, and she hasn't gotten tired of them yet!
I used Bil-Jac Liver Treats to train my Jack Russell. They're made of fresh liver but aren't slimy. You can cut them in half and they last forever.
Also, some pups really like veggies -- my Jack Russell loves baby carrots and fresh broccoli.
Keep in mind with whatever treats you end up using:
Practice moderation in all things. You aren't feeding, just rewarding. A little taste of a treat works just as well as an entire chunk.
Variety in treats will keep your puppy's attention. But your training will be more effective if you always use the same reward when you do formal training because your puppy will make an association with that treat and training.
What I mean is, if you go to obedience class, for example, and always use liver treats, your puppy will learn that THOSE treats mean "we're getting serious." Use other treats as rewards at home when practicing. Make sense?