I am not an expert on Glorantha by any stretch.
But when we started playing RQ we started with this stuff:
Wayne's World of Books - Sci-Fi & Fantasy, Foreign Language, Role Playing Games, History, Maps
River of Cradles
Sun County
Strangers in Prax
Are good resources for just playing. Lots of characters, maps, and scenarios.
These are all based on RQ3.
I don't know what MRQ has out.
Here are a couple of other websites.
Etyries.com - Nick Brooke's Home Page
Simon Phipp - RuneQuest/D100/Glorantha Home Page