How do I sell digital downloads without startup cost?

I'm looking to sell a piece of software I wrote but I don't want to sell it on ebay and I want to checkout using payza or skrill.
I've seen payment gateways that allows people to pay using a credit card but they have an up to 40$ monthly fee or they don't accept skrill/payza.
Can anyone recommend a good site i can use to allow people to buy software downloads?
I've had four people asking about it so far but when I told them to "transfer the money manually" they get a little discouraged and don't reply anymore.

Try ejunkie, I used that in the past, although I'm not sure what their costs are now.