What is the size of a small oleander vs the regular and where can one get some.

I'm not sure about the small vs. regular, but I have seen them at Home Depot, although it was in early to mid spring.

Any decent size nursery (like NorthHaven Gardens) will have them. Do a Yahoo or google search on them for different varity types and sizes.

I wasn't aware of the small/regular distinction. We had one at our other location. One of our neighbors has one and it is in full bloom right now. Beautiful I'm sure that if you are a pet owner, you are aware of the toxicity nature of the plant.