I have a mobilemate sd card reader, and a sanyo hd camera. When I plug everything in nothing pops up? It does not register the device so how do I upload the video from the SD card.
Is the camera set to Play/VCR when connected to the computer and having the SD card inside (if you mean that by everything plugged in)?
What does the Finder show, if you have the SD card in your card reader? It should show as external device, from which you could drag the video files to your hdd.
And if the video could be imported into iMovie, I don't know, as you haven't stated the specific model.
Here is a list for all supported cameras in iMovie '08 and '09.