Buying Ripple or any other cryptocurrency is very easy these days. You have a lot of great options including Coinbase. You can directly buy Bitcoins using them, their prices and support is good as well. read more
I've checked on a few sites, and it doesn't mention for Washington State. read more
Once you have Bitcoin or ethereum it is pretty simple. Just transfer to binance or use services like shapeshift/changelly to buy ripple. Now transfer the ripple to hardware wallet or wallet where you own private keys. read more