Bruce Harrington posted on the Sonex Builder's Yahoo Group, and adding in my own items, I assembled a list of extra hardware I felt was needed above and beyond the Sonex reccommended hardware kits. Note, this list may not be accurate, it's just what I came up with.
All of this extra hardware can be ordered from Wicks or Aircraft Spruce, and the rivets are best ordered from Sonex to get the best price. The good news is that this will only add a few hundred dollars to an otherwise excellent and comprehensive hardware kit.
Additionally, here are the componants I bought for my electrical system.
As with any project, each builder buys their own type and brand accessories required to complete the project. I kept a partial log of my purchases to record expenses and installed components.