Icon Design (Multiple Platforms)

We are in need of icons on multiple platforms for a personal file encryption program. Platforms include Windows Desktop, Linux Desktop, Mac OS X Desktop, Windows Mobile (6.5 and earlier), Windows Phone (7 and later), iPhone, iPad, and Android. The first release of our program will *only* include Windows Desktop, Mac OS X Desptop, and iPhone/iPad. Windows Desktop is composed of Windows XP, Windows Vista, and Windows 7. This implies Windows will need the boring 16x16, 32x32, and 48x48 for older XP systems *and* Vista style icons with an alpha channel. iPhone/iPad will need, at minimum, a 57x57 icon. Due to cross platform support, we will need both PNG and ICO files. The successful bidder is expected to know the minor details that has not been specifcally called-out in this brief description. That is, we expect a successful bidder to have mastery in the area.