Are you sure the card itself is not working? You can try putting it back in the phone (if you removed it) and then plugging the phone into your computer. From there you should be able to use the computer to access the files and information. That is, of course, if the card is still readable.
If it won't register in you phone, when hooked up to a computer, you might want to try the SD card in another phone and see if it registers the card. If it does, you can still follow what I listed first to transfer the files, just using the different phone.
IMPORTANT NOTE: If you try the SD Card in a different phone or other device, Please make sure you do not let that phone/device format the card when you put it in. That will completely erase all the data.