Did you ask for help?
Most of the people I see complaining about getting no help (in an IH or out), never actually asked for it.
Yeah, there are a few things you should know for gafhouses.
1. If you are new, STATE THAT YOU ARE NEW ASAP.
2. Ask questions, and a lot of them, especially if you are new. How should I build this guy? What items should I get? Where should I lane?
*2a. Be aware that some people don't exactly give the best advice (due to lack of experience), but for the most part, no one is particularly out to troll you. Most players have good intentions when trying to inform.
3. GAFhouses vary wildly in skill levels. Play and identify the different skill levels between players. As more people get in, we'll be able to separate newbies and vets. Keep this in mind. I don't mind sitting out if it means it'll be a better game for everyone else overall, just ask. Usually I sit when there aren't enough players to get a game going, or if I haven't played in several games.
4. There are certain players you should look out for if you're a new player joining inhouses. Note that the following list is not comprehensive, nor for the negative groups does it mean the players listed aren't fun to play with or cool people in general. It's just something to keep in mind if you're looking for help or looking to not get yelled at. And this is all from my own experience, I can't see how they act when they're on the opposite team.
Most salty/ragey players: rac, n0b, iA.termyte, iA.fragnat, kapura, Gezza, PuppetYuber
Most common throwers: HyunA, Sanjay
Most pleasant players: Botolf, kagete, Phandy
Most helpful: ksan!, Archie, Ikuu, DrKirby (even if he makes a lot of mistakes)
Most hilarious to listen to on mumble: Archie vs Neki vs Kagete, rac, Meteorain vs Sanjay
Most likely to call you Archie when you aren't Archie: Lirlond