I'm looking into complete systems to manage product sales, develop affiliate programs, and pay commissions. I know Rapid Action Profits can do all this for $200 initially, but the learning curve is steep.
As well, to get a robust system I'm told there are numerous plug-ins necessary, and this greatly adds to that cost.
Another option is, of course, Clickbank. While relatively simple, it has its own issues.
After that, Nanacast is $100 a month.
What else is available?