My landlord is putting the house I am renting on the market. As the Tenant, what rights do I have for establishing guidelines for entry into the home for viewing by prospective buyer/Realtors?

These are generally listed in your lease. For the most part, they are required to give you reasonable notice (usually considered 12-24 hours) that they will be bringing a prospective buyer by.

If you have a lease you at least have something to go by. I don't have one & am in the same boat as kfry1234. Just cooperate as best you can with the realtor. He or she may be able to help you. The realtor doing the showing for my landlord told me he has some properties, but I doubt they'd let me rent from them as I only pay $525/mo. But, he knows my situation so he's keeping an eye out for me. If you're helpful it could get you a good recommendation from your landlord when you need it. He may even be willing to help you out in some way.