Snort is an IDS.. designed to prevent intrusion, not facilitate it. There are some Mac (OSX) tools that simplify the task of cracking WEP (relatively easy) and WPA (harder and time/cpu consuming) more than the Linux tools (that they're based on) but even those aren't straightforward. I've used KisMac successfully before but it needs a real-mode wifi card, not the standard stuff built-in by Apple. If you're on Windows you're screwed, about 99.999% of tools are unix based as the driver model allows easy access to the raw data from the network. Windows' driver model and less than awesome wifi support makes things much more awkward to code around.
SDB