I am a licensed card holder in Washington - But how do I get the seeds?

lots of local breeders with seeds in shops . . . . .

go too seattle lots of co ops/ dispensaires

There are plenty of sites that sell all the strains, sativa and indica, any person could ever want and that certainly ship to the U.S.

check out
http://www.cannabis-seeds-bank.co.uk
http://www.420-seeds.com/
http://www.amsterdamseeds.com

those are just a couple but there are many, try using google if you dont like what ive suggested.

The reason you dont want a male in your grow room is because they produce pollen sacks instead of bud. Its the bud on female plants that contain the THC and CBD's aka the medicine. If you allow a male to grow with your females it will pollinate the female plants causing them to stop focusing on producing Bud, or in other words to stop producing THC and CBD's (again the medicine) and to instead focus on producing seeds. This is how mids are born. And if your not a breeder of cannabis then most likely your seeds would produce poor plants, aka bag seed. IF your goal is to grow really great medicine for yourself then your best off ordering seeds from a site like those i suggested and if you want to continue to grow any one of the strains you purchase then your best bet is to take cuttings from a mother plant. For more info on this simply do a search for "cloning".