A lot of places you will find out about through quests.
For example, the kingdom of miscellania. I never would have even found out about the potential reward from that mini game had I not been told about it by a very knowledgeable friend. She was telling me how she was making loads of money and she didn't even have to do much work for it.
The reason I didn't know about it, is because I'm not really the questing type, unless I have to do it in order to do something specific that I fancy doing at that point in time.
The problem is, it's not as simple as doing that quest and then having access to those rewards, oh no. In order to do that quest, you have to have completed several other quests, which in order to do those, require you to have completed several other quests. That's not all, most of the time, you're required to have a certain skill level as well.
All of this takes precious time, unfortunately we can't all spend all day every day at the computer, so you need a walk through for runescape, to show you how to do everything quickly and easily.
That's where I aim to fill the void and give you a helping hand :)
Here's how the kingdom of Miscellania works.
You have to complete at least 1 quest to have access to the kingdom of miscellania, the "Throne of Miscellania" quest. If you want maximum profit from your kingdom, you should also do the "Royal Trouble" quest, to increase the amount of resources you can collect.
Now, once you done those quests you can start to reap the rewards of your efforts.
First of all, I suggest you put at least 2 million gold into your kingdom. I know it sounds like a lot but it's well worth it, as you can more than double your money every week. The absolute minimum that you should have in your kingdom is 750k gold in any one day.
Your workers will take 10% of what's in your kingdoms treasury every day, and 75k per day is the maximum they will take, hence my recommended minimum. Any less than that and you wont make nearly as much profit as you could be making.
Now, you have to keep your kingdom approval at 100% every day for maximum profit. How to do this? I recommend chopping maple logs on miscellania, it's quick and easy, it's also next to the kingdom so you wont have to run far :)
Your approval drops about 1% a day, so make sure you visit your kingdom every day to cut logs and keep your approval high.
After about a week, check up on your kingdom and take out what they've gathered so far.
You will have gathered up resources far cheaper than market price, about 50% cheaper in some cases and can sell them all for a profit. Also, since you waited a week, you'll receive bonuses, such as rings, birds nests and tree seeds that can sometimes be sold for about 180k each.
I hope that I've shown you something useful with this walk through and I hope you make lots of profits in the near future :)