Software/driver for the 3DS capture: http://3dscapture.com
Software/driver for the DS capture: http://3dscapture.com/ds/index.html
If neither of those work for you (or aren't the site that you remember buying your console from) then go tohttp://www.3dsvideocapture.com
[Katsukity's site] and ask them for the software.
This forum is *not* affiliated with Katsukity, so that's why it's important for you to know who installed your capture card. Loopy's software will not work with Katsukity devices and vice versa.