Floppsy never really took to many store-bought treats as well. I used to mainly give her parsley, celery, carrots (the big ones), and yogurt drops. But sometimes I'd "mix it up" and give her an apple or other fruit. Not all at one time of course. I can't really recommend anything other than what everyone else has told you, because I was never really 'creative' when it came to her treats. But I agree with Karen, watch the amount of sugar in the treats you give her. Good luck!

(If only I could consider lettuce and carrots a treat.. )