I'm not at all sure how this site works yet (I've gone only on traditional forums), so bear with me please if I do something foolish. I'm being drafted to the IDF in a few months and I need to learn Hebrew very quickly if I want to avoid being put into a program for foreign speakers. I currently reside in the US, but I've previously lived in (and have citizenship of) both countries.
After experiencing the government-sponsored Hebrew programs, I totally refuse to accept such a ridiculously inefficient and traumatic method of teaching a language. When I get enlisted, I'll want to focus whatever little time I have left on studying more important things. Something that will damage me psychologically, not to mention take up huge amounts of time and effort, will take away any opportunity I might get.
I can speak a few basic phrases in Hebrew and and can understand a bit more. Immersion is not an option for me currently. My attempts at teaching myself the language have been stunningly misguided (which is to say, like reading Atlas Shrugged to get a proper understanding of Objectivism) and I'm not interested in a lengthy trial and error process. Obviously getting literature on language acquisition is out of the question. I wouldn't even know where to start.
So, I'd just like some methods or heuristics for picking up languages as fast as possible. (I am extremely literate, so there's that.)
I've found myself in a very similar situation last year. I had to go from nothing to fluent in Dutch in 7 weeks in order to be able to study there. Already knowing German as a similar language certainly played a role in making this possible.
Here's what worked for me, in order of importance:
As you probably guessed, conversation is the key. I traveled to different people I knew in the Netherlands for several days each just to talk to them. They were very willing to help. I don't know if you have this possibility, but it would be hugely beneficial. For most of the time I couldn't do this and had to learn in other ways.
Starting with the most common 100 words. These account for 50% of all communication. Then move on to the most common 200 (75%). Work your way up to 500 or more. These lists can be found online. Learning vocabulary lists other than the most common words can be very inefficient.
Your most important phrase should be: "How do you say X?" (in Hebrew)
On reading: Reading can be quite effective. I borrowed some books, read them, and looked up every word that I didn't know on my laptop. I put all the important ones into spaced repetition software.
On spaced repetition: If you have to learn stuff very quickly, you can get the software to ask you earlier than scheduled. I personally used Phase 6, which is a German program, but this should be possible in Anki too.
On grammar: I personally spent very little time with it. It just came by itself, although I did spend some time on dutchgrammar.com. Don't necessarily take this as advice, since I may have had a big advantage - German and Dutch grammar are quite similar.
If your Hebrew is enough to write something, write texts about anything and get a native speaker to read it and correct it for you. This has been immensely beneficial for me, because this way I could see the specific errors I was repeatedly making.
As mentioned in another comment, listening to children's music can help. I personally found listening to children's audio books very useful (Disney stuff), which could be found online. Later I switched to science podcasts.
Basically, spend all of your time with the new language. Always think in Hebrew. When you get stuck thinking, because you miss a word, look it up in a smart phone app or pocket dictionary. After a long day your brain may feel like it has melted. Aim to get that feeling every day.
Here's is a pretty good article on learning a foreign language. It contains some of my tips: http://markmanson.net/foreign-language
This. I don't get why so many language courses teach you (say) the names of a dozen different foodstuffs before teaching you how to say “one of those”. IMO that's silly.