1) As others have said; look at the admin interface to see if it's hung/borked or if the line is unhappy. If it claims to be connected ok then traceroute (I prefer mtr, but you'd have to install it) can tell you how far your connection is getting. It may not be a problem on your end at all, but this is where you can get more information about that.
2) Overheating (make sure all devices and their wall warts have decent air-flow and are in a fairly cool place), external interference, bugs (if packet type X arrives right after packet types Y, D and Q... hung airport). Make sure the firmware is up to date (via the airport utility on da mac), try changing the channel manually (only 1, 6 and 11 are worth using). iStumbler on the Mac can tell you what other channels things are using in your area, use the least used one.
3) Unlikely but possible. If one device is wedged then rebooting a directly connected device could free it up... but yeah, rather unlikely.
Be methodical. My usual routine when something goes down is to check the computer is getting an IP, traceroute/mtr to www.google.com or similar and see how far it gets (if it fails, traceroute to an IP to see if DNS is failing). If it fails inside my network, try wired net. If it never gets ouside the house, check the router's information. If that doesn't respond, powercycle it.
no subject
2) Overheating (make sure all devices and their wall warts have decent air-flow and are in a fairly cool place), external interference, bugs (if packet type X arrives right after packet types Y, D and Q... hung airport). Make sure the firmware is up to date (via the airport utility on da mac), try changing the channel manually (only 1, 6 and 11 are worth using). iStumbler on the Mac can tell you what other channels things are using in your area, use the least used one.
3) Unlikely but possible. If one device is wedged then rebooting a directly connected device could free it up... but yeah, rather unlikely.
Be methodical. My usual routine when something goes down is to check the computer is getting an IP, traceroute/mtr to www.google.com or similar and see how far it gets (if it fails, traceroute to an IP to see if DNS is failing). If it fails inside my network, try wired net. If it never gets ouside the house, check the router's information. If that doesn't respond, powercycle it.