Under the hood is the fuse panel, drivers side. Check to make sure you're getting power through the fuse and through the terninals. You may have to un bolt the fuse block to make sure power is going through.
The socket's in question, would be the bulb sockets in the tail lights. Check and see if you have 12 volts there. If so, you may have a ground issue.
The T/S combination switch is the turn signal/4 way flasher switch under the steering wheel. This would be the last thing to test, however I have seen where the 4 way button has been lodged causing these symptoms. Play with the switch alittle to see if your problems are caused by it.
Check your owners manual for fuse locations as there may be more than one for each circuit.