Ask for something that is not here yet. The more people who ask for the same thing, the sooner it appears.
Requests go into one list. Anything asked for by several different people moves up it, and the ones at the top get looked at first. That is the whole system. There is no way to pay to move a request up, because there is no way to pay for anything here.
A request that names a specific version and says why that version is wanted is far more likely to be filled than one that names a program and nothing else. Older builds in particular are usually wanted for a compatibility reason, and knowing what that reason is makes it possible to find the right one.
The requests being worked on at the moment are for engineering and audio packages, along with a run of older office and operating system builds that several people have asked for on compatibility grounds. When one is filled it appears on the updates page like everything else.