Coinbase Digital Asset Exchange
Coinbase will for a fee sell you crypto currency at the going exchange rate. Primarily Bitcoin (BTC) Ethereum (ETH) and LiteCoin (LTC). Connect Coinbase with your banking information and transfer funds to purchase BTC,ETH, or LTC. And now Coinbase allows credit card transactions for instant purchase.
Sometimes Coinbase offers deals for new account holders and for people who refer new accounts. Registration is pretty straight forward and there is also an app for smart phone use.