Not a good idea. Perhaps through networking and passing it along by word of mouth from one grower to another but as far as full scale market....naw.
See if the new federal law passes, then it should be fine in a state that has mj legalized. If they let you grow, buy, smoke, then what difference it would make if someone sells seeds. They can gain revenue on a license like that. It might be couple more years till the law makers grasp it though.
Not worth the trouble at the moment. Sending marijuana seeds is still against the law in many states. While the fed has stated that they will not pursue cases where individuals are in compliance with state medical marijuana laws they have made it clear that product is meant to stay in the state where it originates. One caught shipment to a non med state with a over zealous prosecutor could easily mean jail time. Add to that the fact that banks will not do business with cannabis retailers. Its a major problem here in co. Sure you could do cash only but then you are still looking at tax evasion and / or money laundering because you damn sure cant report your new found illegal income. Several have tried what you are asking, most are gone now.