Hi Langisto - welcome to the forum!

First, there is no way to cable a USB drive or a USB memory stick to the dock of the iPad (the CCK is needed but is for use w/ a digital camera or its SD card). Second, as Richard has stated - cloud storage or other Wi-Fi options can be used to store your files (especially larger photos, movies, & music) - take a look at just one option by Seagate
HERE; also, you might want to search the forum - there are plenty of threads discussing this topic along w/ comments on setting up Wi-Fi hotspots that can also permit storage choices - good luck!