I hate to break the news to you, but the ball is not worth very much. I"m guessing you'd be lucky to get $100 for it. While there are some great names on it, collectors prefer single-signed balls, team balls or a group of signatures built around a theme, i.e. Hall of Famers. The truth is the ball would be more desirable if it was only signed by Killebrew, Snider or Oh.
If you're looking to sell it, I'd recommend Craigslist first at a set price. You might as well ask for, say, $300 for starters and see if you get any takers. You never know, beauty can be in the eye of the beholder. If you put it on eBay you'll probably get what it's worth, whatever that may be.