> Ultimately, my question will be: Can I use these icons (both as-is and > modified versions) as elements of a site I am building?
If it's the SVG Crystal icon set, yes you can. It's released under the LGPL which in this case is interpreted so that if you change the icons, you must release the changed icons under the LGPL but otherwise there aren't much restrictions. I think this was covered in some SVG Crystal FAQ file in the net. - Jarno
