There's certainly a good market for the right product at the right price. PLease have a look at my website for some examples:
http://www.sandrila.co.ukYou will need a website, a good description of what you offer, samples that can be downloaded and installed, an eCommerce system to take payments for you and a download system so buyers can get their software immediately (th eCommerce provider may supp[y this).
The Office Marketplace seemed a really good idea, Microsoft had prepared it for expansion for markets in New Zealand, South Africa, Ireland and India, I was all ready to go ... then the whole Office Marketplacle got stopped. No more editing allowed, so now all my listings are out of date and showing incorrect information.