I started using RW in November and went through the same thing as you—not knowing where to start. Some tips you may find helpful:
First decide if you are going to use RW to build an entire world or primarily just for adventures.
The reason I say this is if you intend to build a large detailed world or campaign, it would help to start with the big elements (realms, regions, cities, gods, etc.) and work down. That way you'll get more out of the autolinking. You don't need to enter all the details for each topic, just outline the major elements of your world/campaign, so that you have the titles created and linkable.
When you get to creating adventures, the story board is the place to plan out the adventure and then you can create scenes for encounters from there.
Don't worry about filling in every field.
You can always go back and fill in more detail. Also, if you have a lot of empty fields you know you'll never need in a topic you can easily remove them using Ctrl+` or Ctrl+Shift+` to remove empty snippets and sections.
Don't worry about picking the "wrong" topic type.
RW is designed to support any game system and DM style. That flexibility, however, can create a kind of analysis paralysis. Read over the reference materials so you have a general understanding of the different topic categories and just go with it. If you later decide that you should have used a different topic type for an item of content, you can always change the topic to a different category.
Browse the Forums
These forums are a great resource. No only for the help you can get from the very active community, but also the knowledge base it has become. For example, look at the thread "I want to see a complex realm." Start with page two in that thread, or just use this link:
http://forums.wolflair.com/showthrea...t=52565&page=2
AEIOU and Exmortis have shared screenshots that will help you see how some more experience users have organized a lot of detail in RW.
I really think that there needs to be a reference manual and videos that SHOW examples of realms using the various approaches the realm making rather than just writing about it. A serious of videos of users giving a tour of their work in RW would be very helpful. In the meantime, the screenshots users have shared in these forums are the next best thing.
Make copies of topic/article templates before customizing
I like to customize my topic and article templates to contain the fields that make the most sense for the ruleset I use and for my campaign. It is tempting when starting out to remove protection from the default topics and customize them. If you intend to eventually buy content from the content market, however, that may create issues. Also, you may later determine that the default was better. Instead, create a copy of a template, use that copy to make your custom template and hide the original if you don't intend to use it.