At Maker Faire or two ago I bought the Voice Shield kit that is produced by SpikenzieLabs (http://www.spikenzielabs.com).
It fits on top of the Arduino and only uses a few pins of the Arduino so there are lots of other pins available to do other things like trigger a sound, or whatever.
It is based around the ISD4003. (I have used the ISD2560 in previous projects).
I was a little intimidated by the instructions on how to get the interface up and running, but I eventually figured out what I was missing and then it was pretty easy.
Basically you load the ISD4003 with sounds using the separate program, (available from their website) by sort of giving the words a number. Then after that, that program is gone and you can play them using by calling the numbers in your own program.
There are some code snippets there to sort of give guidance.
It actually sounds better than the ISD2560 and it comes with a small amplifier so testing does not require you to build an amplifier to hear things. I found trying to take the sound from my computer wasn’t so easy. There was some crackle noise coming through the computer which was also being recorded. I used my MP3 player and took the output from the headphone jack and the sound was very clean after that.

I made a carrier board to take some inputs from the Voice Direct speech recognition module.
Here are the electronics that I plan to add to the 1812. There is a servo motor, a speaker, a Sharp gp2d12, Voice Direct module, Arduino and Voice Shield. Missing are the batteries and some LEDs.
