[CentOS] Configure wireless USB ethernet

I have a system that does *not* have a graphical desktop installed, nor do
I ever plan to.  I have its wired ethernet working just peachy.  Now I want
to configure a USB wireless ethernet and scratching my head.  Particularly
since I don't use NetworkManager, everything is manually configured.

That said, if I enable NM, I see this in /var/log/messages:

NetworkManager[26900]: <info> rfkill0: found WiFi radio killswitch (at
/sys/devices/pci0000:00/0000:00:1d.7/usb1/1-2/1-2:1.0/ieee80211/phy0/rfkill0)
(driver rt2800usb)
NetworkManager[26900]: <info> WiFi hardware radio set enabled
NetworkManager[26900]: <info> WiFi enabled by radio killswitch; enabled by
state file
NetworkManager[26900]: <info> WWAN enabled by radio killswitch; enabled by
state file
NetworkManager[26900]: <info> WiMAX enabled by radio killswitch; enabled by
state file
NetworkManager[26900]: <info> Networking is enabled by state file
NetworkManager[26900]: <info> (wlan0): driver supports SSID scans
(scan_capa 0x01).
NetworkManager[26900]: <info> (wlan0): new 802.11 WiFi device (driver:
'rt2800usb' ifindex: 4)
NetworkManager[26900]: <info> (wlan0): exported as
/org/freedesktop/NetworkManager/Devices/1
NetworkManager[26900]: <info> (wlan0): now managed
NetworkManager[26900]: <info> (wlan0): device state change: 1 -> 2 (reason
2)
NetworkManager[26900]: <info> (wlan0): bringing up device.
NetworkManager[26900]: <info> (wlan0): preparing device.
NetworkManager[26900]: <info> (wlan0): deactivating device (reason: 2).
kernel: ADDRCONF(NETDEV_UP): wlan0: link is not ready
NetworkManager[26900]: <info> (wlan0): supplicant interface state:
starting -> ready
NetworkManager[26900]: <info> (wlan0): device state change: 2 -> 3 (reason
42)

Looking at 'lsmod | grep rt' I see:

rt2800usb              18780  0
rt2800lib              71865  1 rt2800usb
crc_ccitt               1717  1 rt2800lib
rt2x00usb              12696  1 rt2800usb
rt2x00lib              48438  3 rt2800usb,rt2800lib,rt2x00usb
mac80211              552581  3 rt2800lib,rt2x00usb,rt2x00lib
cfg80211              619515  2 rt2x00lib,mac80211

And lastly ifconfig shows the interface present:

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:1401 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1401 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:177957 (173.7 KiB)  TX bytes:177957 (173.7 KiB)

wlan0     Link encap:Ethernet  HWaddr 00:87:35:1C:07:BF
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

Great ... now how do I configure this sucker?  When I turn NM off, that
interface disappears.  I'm assuming I can create an 'ifcfg-wlan0'
configuration but what do I need to put in there so it knows to connect to
my home wireless (with password) and all of that fun and exciting stuff,
and continue to do that over a reboot.