I have a set of replacement icons available here:
http://www.hicksdesign.co.uk/journal...for-omniweb-55
There are 2 button options, Safari (Square) and iTunes (round), and they change a variety of icons, not just the toolbar. I'm currently working on a new improved version that uses colour icons rather the 'monochrome button' style, but it could be a while before I finish that.