If this is just tricks (as in the sentry thing) and tips (as in building/event hints and help), then this should be easy for everyone to add to.
Things like, SuperShift, allowing you to move a brick by it's entire dimension in a given direction, which makes repetitive building faster.
Enabling ID's in the Options menu if you want to know someone's ID in order to add it to an event, such as the JVS Doors.
How to use relays to create continuous rows of events.
How to use Delays, knowing that a second delay is "1000", not "1".
How to use toggle events in order to make on/off buttons, like the light switch in the Bedroom Map's Demo House.
How to pilot the Flying Carpet, Flying Wheeled Jeep, and other flying vehicles.
How to view text and playerchat that has disappeared off of the screen, using the PageUp button and the PageDown button.
How to set up named bricks so that you can have a button that makes another brick do something, as well as any rules that go along with named bricks (For example, the named brick having to belong to you, and you have to have been the one to have built it).
Maybe some small hints as to where to get to the Default Maps' hidden areas.
Including a small hint to the hidden area in the Tutorial.
Maybe integrate some forum aspects into this too.
For example
Did You Know You Could...
Ask on the Blockland Forums for help, whether that's a problem with your game, like it crashes, or a suggestion/request that someone should make a certain item, or you can ask for Ideas on what to build, if you are stuck.
How to use coloured text in Client Events, as well as text with different fonts.
And perhaps, how to apply colours and fonts to your server's welcome message.
What Add-Ons are good to start with.
Where to download RTB, a brief summary of it, and how you can download files from it in-game, on the RTB website, and in the RTB Listing on these forums.
Those are just a bunch I've got.
And I know I'm missing more.
Just put these to more detail.
Include some pictures so that newer members can understand what to do better.