A LARPing we will go, a larping we will go..
Yes I used to be in a LARP before I left San Diego about 7 years ago. I wasn't into the "vampire" scene but I like the intrigue as far as a role playing scene. My friends were running a LARP and so I took part in that for about a year.
A LARP is like any other role playing you do accept you do a lost more role playing and interaction with people. Combat, skill rolls, and the like are made using a system of rock/paper/scissors. Depending on your skill level you can try again if you fail by "overbidding" someone.
You will still have a character sheet, some groups do costumes to various extents. Costumes are usually done in places where there are not a lot of people to freak out.
Watch the group of people you want to LARP with first for a session or two to make sure they are going to be people you want to play with.
As a funny LARP story, this was the last game I was in (it gets geeky and probably has spelling errors since its been a while). The moral of this lesson is that there are more ways out of a situation than simply attacking them head on.
My character was from Clan Tremere and his background was Dan Smith, former Astronomer, now a vampire, so he was nerdy and into science and magic.
A fairly new player decided to make it known he would not follow anyone if they could not defeat him and was challenging everyone in power. The player was a combat monster and no one had one. Being the only (known) Tremere I would be challenged at this, my last game before I moved away.
In the world of LARP you can do things to "prep" before a game session and between sessions that you work out with the GM. In this case I had been saving blood which I can use in magic. I found out from research this new player was playing a much older vampire than me. So I figured I had enough blood saved to lower my "effective" generation below his.
Next I asked permission to accept his challenge and it was granted. I then asked the GM on clarification of the rules, if I am challenged do I get to choose the method of combat, I was told traditionally yes. I asked for a particular book.
The stage was set, the new player challenged me and later that evening about 20 other people were there to watch the bloodbath. I stood before the new guy and verified that if I was the challenger then I could choose the weapons, and I was told yes. I called to a friend to bring me my book (it was just a prop). I opened the book and said:
"Very well then. This is a list of stars in a cluster near our own. I will allow you to choose any star you wish, the first one to calculate the distance to the star based on its redshift is the winner."
The player was stunned, "You can't do that."
The GM said "Oh yes he can."
There was nothing he could do, he had no science skills and lost the contest, I had beaten him and not gotten killed.
I then said "Command word, grovel."
The player smirked, he can't do that I'm older than he is.
The GM said, "Oh yes he can, he's older than you right now."
"Magic," I said.
Later that game the player thanked me for a lot of fun. Too bad I had to move to the bay area after that game.
Hope this helps.