Several years ago mid sized companies (usually consumer products like beverages etc) would agree to part with some funding in exchange for wrapping the touring vehicle in their logo and / or having the artists shoot footage of them in various parts of the country using their products but this is a rather hard call to make in this economy and with everyone and their mom looking for similar handouts. Still – if you guys use a non traditional product it might be worth a call into some marketing departments at various companies especially if you happen to know someone inside (Think clothing, beverages and other products that lean heavily on "lifestyle" marketing)

Other than that you could seek an investor either directly for what some call a 3F raise (Friends, Family & Fools) or go through a company like sellaband.com

No easy way to do this I’m afraid. If you can’t fund the whole tour remember that starting to tour in concentric circles around your home market is a great way to begin to expand your reach. That said if you already have a regional draw you could always find like minded people in the market you want to tour and see if you can trade them an opening slot for an opening slot.

I hope that helps. Please visit my site at the URLs below – I try to post information of this sort on a regular basis.

Very best,

Rick
References :
http://musiciancoaching.com/music-business/how-to-make-it-in-the-music-industry/
http://musiciancoaching.com/music-career
http://musiciancoaching.com