Neighbor dog attacks my dog as we walk

Question
While walking my puppy, my neighbor's dog, which is always loose, runs up to us and nips at my puppy. We have asked the neighbor to keep the dog confined but she ignores us!
We are in a rural area with no lease laws. Is there a spray I can use to deter the nipping Neighbor dog?

Answer
Hi, Glenn!

This really is not my area of expertise, but I found a couple things that may help.  Check these out:
http://www.gooddeals.com/products/100/Dog-Off-Portable-Bark-Free.aspx
or http://www.cooldogtoys.com/directstop.php
The first option is an electronic device, but it may not serve your purpose, since your dog will be with you - but may be worth a look.  The second is a spray, which claims to be humane, so may work in your case.  Good luck!