It would help if you could be a little more specific about what you were trying to do. I assume you are looking for a suitable power supply to run your Pi.
To condense what was said above....
Power supplies are rated by voltage and current. The voltage is the nominal voltage, and the current specification is the maximum amount of current that *CAN* be supplied (maintaining the nominal voltage). That being said, a power supply with the specifications you listed won't pump 10amps into your Pi. It just means that you will have 10A available to run your Pi along with a stack of USB external drives.
A word of caution: 10A is quite a bit of current for most PCB traces to handle. Yes there are fuses built into your Pi to protect it, but if there is any kind of short between the fuses and the USB connector you're going to get a big surprise.