First make sure you have a good plan for support. Either you have the cost of support built into your product price or you offer various support packages to purchase on top of the software. People who are going to sell your software for you will want to know it can be supported.
Also, be careful with agreements you make with resellers. If possible stipulate a lower percentage for them on future upgrades since it is your job to keep the client happy, hence you should profit more even if they got the original sale.
As for logistics you probably need a plan for servicing the sales group. If it's online downloads you are selling make sure you got people taking care of your servers. If it's packaged DVD's show that you understand the costs and you are ready to scale if sales scale, that will give your reseller confidence.