so i have madwifi installed for my d-link (Atheros AR5212 802.11abg NIC). how do i switch so my internet traffic goes through that card instead of my wired connection? im not sure everything is installed correctly, this is the output from ifconfig

ath0 Link encap:Ethernet HWaddr 00:0F:3D:A9:1A:38
inet6 addr: fe80::20f:3dff:fea9:1a38/64 Scope:Link
UP BROADCAST NOTRAILERS RUNNING 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:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

eth0 Link encap:Ethernet HWaddr 00:11:5B:F5:53:CD
inet addr:192.168.1.106 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::211:5bff:fef5:53cd/64 Scope:Link
UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1
RX packets:4647 errors:0 dropped:0 overruns:0 frame:0
TX packets:4636 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1890225 (1.8 Mb) TX bytes:479243 (468.0 Kb)
Interrupt:217 Base address:0x6000

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:26 errors:0 dropped:0 overruns:0 frame:0
TX packets:26 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1604 (1.5 Kb) TX bytes:1604 (1.5 Kb)

wifi0 Link encap:UNSPEC HWaddr 00-0F-3D-A9-1A-38-00-00-00-00-00-00-00-00-00-00
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:40 errors:0 dropped:0 overruns:0 frame:10
TX packets:16 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:199
RX bytes:3352 (3.2 Kb) TX bytes:739 (739.0 b)
Interrupt:66 Memory:ffffc20000b60000-ffffc20000b70000


im assuming my wireless connection is ath0, but what is wifi0? what other commands are usefull for wireless connections... i know iwlist scan will give me the avalible connections, but i dont really know much more...

iwconfig, ifconfig and dhcpcd are your freinds

you can set you essid and encryptions keys like so with iwconfig (as root)
# iwconfig ath0 essid mywireless
# iwconfig ath0 key 123456789ABCDEFG1234

then if you have dhcp get yourself an ip address by using dhcpcd like so
# dhcpcd ath0

if you don't have dhcp you can manually give yourself an address
# ifconfig ath0 inet 192.1681.10.123 netmask 255.255.255.0 up