I'm Making My Own Solo D&D 3.5 Campaign

[aimlessPolymath]

It's absolutely simple- it's just that you'll have to repeat this process a lot. This is one major city- how many more are there in the whole country? How many countries are there?

Some tools that can help when inspiration starts to slow down:
-Look at the relationship between a location and its neighbors; maybe they're becoming more friendly, or less friendly.
-Consider the location's major industries; an opportunity opening up, or another one closing.
-Consider the locations's demographics; racial, religious, financial, political, or otherwise. Interactions can happen between two of the same type (ex. two races in conflict), or between two different types (nobles cooperating with a particular church).
-It's okay to repeat news from one location to another; the nature of the news shifts from "dealing with news X" in location A to "dealing with location A" in location B.

Note that the amount of detail you'll be putting into different locations varies depending on how much time the players will spend there. You currently have the minimum detail for Herlon, but you'll need to zoom in and look in more detail if you expect the players to spend a significant amount of time there. If the pieces of news are going to be a significant aspect of the game, they'll need more information than things the players hear about tangentially to their adventure, etc.