I bought a powered USB hub (D-Link DUB-H7) and connected it to my GT-P3113 using the USB adapter that came with my new Student Edition. This gives me 5 standard USB ports and 2 with extra power for LOTS of storage. I can connect flash drives, etc. to the standard ports and fat32 hard drives to the hi-power ports. I use a 500GB Samsung usb drive that is full of movies, music, books, apk files... This is much more convenient than changing (and sometimes losing) the micro SD card. 
I originally used this same hub with my Excite 305 until I gave that tablet to one of my grandsons. The Excite could power the same HD directly using an OTG cable, but the GT2 requires a powered hub.

I originally used this same hub with my Excite 305 until I gave that tablet to one of my grandsons. The Excite could power the same HD directly using an OTG cable, but the GT2 requires a powered hub.