Well, a quick search on the Google Play store shows a free program called "Backup Contacts" (what else? ) can backup several ways, including the SD card. Or, run a search on Play store and a bunch of options come up.

You can connect any Android phone directly to a PC/Mac through USB and run as an external drive. Or, if you have the hardware, just take out the SD card and plug it into your computer. Transfer the contact backup file (and pics) directly to a computer.