I'm confused on if I can replace an 15 amp receptacle with a 20 amp
receptacle. I want to be able to hook up a espresso machine in my
kitchen
and the machine requires a 20amp circuit.

The particular circuit I want to change out has a 20 amp breaker coming
from
the box using a 14 gauge wire to, 1 15 amp GFI receptacle & 2 15 amp
receptacles in the kitchen.

Do you mean a recepticle rated for 20amps, or one with a 20 amp plugin? The
20 amp plugin has one of the blades turned 90' (See
http://www.hardwarestore.com/media/p...9_front200.jpg)

You should *NOT* install one of those 20 amp plugin receptacles unless you
know that the whole circuit is on 12 gauge wire and on a 20 amp breaker.

Now, if you want to just user a higher rated standard outlet (See
http://www.electronicsoutfitter.com/...-5325-wsp.jpg),
that's fine.