Dolphin, the GameCube and Wii emulator - Forums

I was just wondering this, or where I could possibly find where the files containing this information is so my friends and I can still have our current data without having to restart

No, you can't have different data in them (unless you set Dolphin to not insert any memory cards or SD cards).

By default, memory cards are in C:\Users\<your username>\Documents\Dolphin Emulator\GC\, and the SD card is at C:\Users\<your username>\Documents\Dolphin Emulator\Wii\sd.raw.