I know what you mean about the logos. I've made some images with the Mint and KDE logos and I always end up having to hunt through my hard drive for the .svg images so I can resize them easily. Of course once I find them I always forget specifically where they are or what they're called so the hunt is on all over again.
I did a quick DuckDuckGo search and found a logo on Wikipedia
and some older "current" logos on linuxmint-art.org
. There's also a Linux Mint group on Deviant Art
that posts some great images that may help out, even if just for inspiration.