This question asks about what you'd need to know to power a Pi from a non-dedicated power source.
It also links to the Quick Start Guide, which says:
Micro USB power supply – make sure you use a good quality one, capable of providing at least 700mA at 5V. Do not attempt to power your Raspberry Pi by plugging it into a computer or a hub.
Are there any available lists online of power supplies that meet this specification?
Are there any sites with reviews indicating which manufacturers are more reputable? (Does it matter?)
Is there anything else I should know when choosing a power supply?
I'd like to know whether I can just buy the cheapest power supply I find (that provides 700mA), or whether I need to shop more carefully.