finding 100% of either type of strain is going to be mighty difficult. Currently, almost all strains have been crossed, back-crossed, and recrossed with tons of other strains. Remember, a true pure sativa or indica must also demonstrater true indica/sativa phenotypes as well as have the original genetics. Durban poison is a good example of 100% sativa, but it would be nearly impossible to grow inside, and pure sativas aside from being lanky are finkicky eaters, and grenally hae unstable genetics, (hermi very easily) I would reccmoend more indica, but I doubt you'll come accross to many pure starins. NL is good as well as ak47, very easy frist plants. good luck.