I've found a really good blogger who does the Run A Game blog. The person has only been doing it for a year but they've got some good articles up already. The below are my top picks:
Variant Combat Resolutions That Don't Rely On Murder
This contains a good list of ideas including how one might utilise them - from how it might begin to what sort of challenges might be part of it.
Golden Rule Chicken
The article talks about those situations when players try to get their hands on an incredibly potent power to bypass most plots you could throw at them, forcing you to either nullify that power (which won't be fun for them) or run a non-game where they simply state "I unleash Power X."
God Machine Chronicle System Review
An interesting and in-depth look at the new World of Darkness system. Also known as World of Darkness 2.5. This has been really helpful for me as I have put myself forward to run a God Machine based LARP.
Basically the idea behind LARP Storytellers trying to sow discontent between the various characters to cause them to start having a go at each other. After all, the worse thing that can happen with those big multitude of player LARPs is if peace breaks out. There's generally only so much straight up entertaining a Storytelling team can do for 20+ players.
I considered doing this myself but then worried that it might be too clunky. Apparently it's not. Basically you give players little envelopes with information inside and a label on it saying: "Open if X happens" or "Open at X o'clock." The main issue I have with it is where the players are going to keep them. If they're wearing dresses or skirts or even some women's pants, they're not going to have pockets. Other than that, I really like the idea.
Elysium Style LARP Advice
Really good advice on running a social / political LARP. I think the best advice comes from the warning about introducing too much external plot. External enemies have a habit of driving the different factions together and once peace breaks out the game generally dies. After all, there's only so much investigative action that can happen in an Elysium style LARP, which is generally designed for larger groups of players.
Adventure Style LARP advice
This one gives advice on how to run adventure LARPs where the external plot is the focus of the game, such as is typical in a Call of Cthulhu LARP adventure.