What size is your old SD card? What size is the new SD card?
Which phone do you have?
For instance - on an EVO you can go to Menu>>Settings>>Applications>>Manage Applications>>On SD Card You can then put a check mark on any application shown here - meaning it is eligible to move to SD card - and then move it to the sd card.
You could remove the SD card and insert it into a usb reader and copy it to a folder on your pc - then copy to the new sdcard with the usb reader
I just bought a new SD card, because I am constantly getting messages that I don't have enough internal memory to upgrade my current apps. How do I sync my apps on my current SD card, so I can download them again to the new SD card?