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You could go on changelly.com right now and buy ethereum as quickly as you can enter your ethereum wallet address and your credit card details. Coinbase is easy too, but you must first set up a account which doesn't take long, they do want id verification, take good photos of your passport and you should have a verification in a day or so. Also make a small bank transaction to your coinbase account as soon as possible to verifiy your fiat bank account for future investments or exit back to fiat currency ($€£).
Here is a link for the official ethereum project website with more information.
https://www.ethereum.org/

shapeshift.io

you can even hold ether in your blockchain.info wallet

bittrex.com you can also trade there