Releases - This is the main place to keep an eye on for all the information on the latest releases across all the products and contains a link to all the features and bug features in for each of the products. https://world.episerver.com/releases/?page=1
Blogs - I would assume you know this if you're reading this but the Episerver blogs area contains lots of great blogs from experts including Episerver staff, EMVPs and great developers. https://world.episerver.com/blogs/. Also it's really easy to get started blogging, so if you have something to say I'd suggest trying it.
Forums - Forums area the first line place once you can't find what you need in the docs to look, below I'll give some tips on how to get answered. https://world.episerver.com/forum/
User Guides - These are great not only for your QA team and introducing people to using Episerver but as a first line point to give to your clients and their editors. The guides are pretty comprehensive and are a great editing reference http://webhelp.episerver.com/latest/home.htm
The forum should be the first place you look when you can't find what you need on the developer guides or blogs. There's lots of talented people from Episerver, EMVPs and developers around but it's important to maximize how you use the forums.
Search the forum for your question - It's likely someone has posted what you have before so before posting use the search in world to search for your question.
Post in the right area - This may seem simple but try to post in the right area of the forurms, if you're posting commerce post in commerce.
Post the version of the products - When you are posting make sure you include at least the core versions of CMS/Commerce/Find you are using so that people can help debug easier. If it's a complicated question consider posting more
Post example code where possible - You see a lot of people posting question with a few lines saying something like "xxx isn't working as expected, how do I xxx". This really isn't helpful for someone coming in fresh. Post some examples of your code and any touchpoints, if it's not sensitive even consider posting some code for people to run.
Give examples of how to recreate the problem / give screenshots - This is a given for any bugs/issues, give reproducable steps and if possible some screenshots to show what's going on more visually. You can use https://imgur.com/upload to upload the screens online and link to them.
Detail - Finally and this is a big one, don't be vague...Try to post as much information and code as possible. If people are going out of their way to help, make it easy.
Hope this helps, follow these and it'll be easier for us all