Why is it that online digital comic resources like Comixology only get certain issues of things? I have been striving to track down all of Wonder Womans issues for purchase online but only the first nine issues seem to be available...Why is that?

I am not sure I understand this question at all. I just went through and they had hundreds of issues of Wonder Woman. Which nine issues do you mean?

I know the process of converting these to digital, especially Golden Age issues, is laborious and time-intensive. DC and Marvel have been putting their recent stuff up first, and then the back catalog in increments. But I found just a ton of issues from every run, so I don’t know what this means.