I know a lot of people and birds eat sprouts. I sprout things for myself from time to time. In terms of where to buy seeds fit for consumption, all sprouted seeds pose some risk, as the seeds themselves (even organic seeds) can contain bacteria on the inside. There is no way to ensure that the seeds/beans/lentils are not harboring internal bacteria, so there is always some risk when you put them in a non-sterile, moist environment and eat them before the plant matures.
They sell seeds for sprouting at the health food store, but again, these are not a sure bet as far as 100% safety.
I am not telling you not to sprout, but I just wanted to put it out there. I guess it's sort of like eating runny eggs---I do this and I am fine, but there is a chance that one day I won't be lol.