Glad you like the SimHQ Motorsports related articles. And I think you're guaranteed a good time in the company of rFactor and its ever-growing number of mods.
Chunx' recent articles on how to configure your wheel and various in-game settings is a great guide to getting you started.
Part I: Optimizing the Hardware
here Part II: Optimizing the Controls
here Part III: Optimizing the Driver
here Part IV: Learning To Race
here With the number of mods growing each day, it is very hard to keep up with what is up there, even for a "mod-o-holic" like me.
If you go to the rfactorcentral site linked above and look through the different car mods available with an eye to what sort of racing that appeals the most to you, you can start trying out any mods offerig that type of racing.
You can also check out how the mods are rated by the community and read the comments posted for any specific mod. Pretty useful feature, as well as comments about installation and any known issues or bugs.