I have a software product that is unique.  I've had many people ask me
if they could be a reseller of my software.  I don't have a clue as to
how to go about this.  Do I charge them for the priviledge of
reselling my software?  What type of percentage should they typically
earn?  Do I need a contract with them?  Does my pricing structure
change to accommodate their needs?  Do I set quotas for each vendor?  

I believe that having resellers across the country could be a real
boost to my sales but I want to be sure that I am fair - to my company
and to my resellers.  HELP!

We use Regsoft.com services to process credit card payments for
customers who buy our software online. It pretty much only works with
shareware/demoware, where the end user can download something to try
and has to register to get the full version. We were looking at the
same issues that you are and have had some luck signing up some
resellers with an affiliate program that really does bring in
customers, not a lot but every bit of promotion helps:

http://sellshareware.com/About.asp
http://sellshareware.com/LearnMore.asp

I wouldn't set any quotas. The market is so tough right now that
quotas would discourage your resellers. We set it up so the reseller
gets from 10% to 40% of a sale that they generated. With this
affiliate type setup, you don't need a contract with
affiliates/resellers. They signup with sellshareware.com in order to
get paid by them. You also get a check for sales, from Regsoft, which
owns sellshareware, and that means that someone else does all the book
keeping. Been using Regsoft for years to process our online cc
payments from customers. No complaints. Good luck!