I purchased a Nespresso machine; they use capsules and make perfect espresso every time. This is the unit I have:
http://www.amazon.com/Nespresso-D120...1941418&sr=8-7
You can find them on sale -- I paid about $170 for this unit on sale from Amazon a few months ago.
You order the capsules from Nespresso; they have a large variety and they run about $0.55 each in boxes of 10. They arrive in a couple of days.
Before this I had a grinder and a Barista machine which I loved. When it was time to replace the machine I opted for convenience and I have no regrets.