You should be able to get them at just about any garden store. Typically, there are around 50 seeds in each seed packet, and you need approximately 300 seeds for a decent trip. Be prepared to spend about $1 to $2 per packet. The active chemical in the seeds is LSA, which is a distant cousin to LSD. The effects are said to be similar, but much milder. A trip will probably last for up to several hours. See Erowid.org for more details and experience reports. I've never tried them myself, but I have read many of the reports at Erowid. Don't eat the seeds whole! You need to crush them or chew them up thoroughly, since your digestive system is incapable of digesting the tough, outer covering of the seeds.