How do I get into this? where should I start? companies?
For the past two years - or as long as it's existed - Bitcoin finance starts and ends at MPEx (or perhaps a broker thereof).
These are the people who publicly and quite painfully humiliated all pretend-financiers, starting with Paul Graham and his ycombinator dronehive all the way to cardboard media personalities a la Keiser and who-have-you in between. They're the people who implemented the destruction of the various scam exchanges that popped up to date, after delivering proper warnings, they're the people who brought down "bankers" and "rating agencies" and all sorts of bullshit.
These are the people who created all functioning vehicles and instruments in this market, the CDO, the BTC option, the BTC future. These are the people who listed the first meaningful Bitcoin company (Satoshi Dice) and these are the people who created the first, and so far in all these years the only honorable delisting of a Bitcoin company of size. These are the people conducting the ROTA experiment, which demonstrated why the speaking public isn't to be involved in decision making, these are the people that created the AN0 accounting standard, and introduced the use of contracts in business and generally speaking did everything, literally and absolutely everything that exists, matters, and is worth the notice.
And of course the guy behind it, my boss, is by far the richest guy in BTC, to say nothing of the smartest. Even with his million BTC+ wealth, the latter probably enjoys the fatter margin.
I suppose all this seems pretty incredible, but that's okay: if you have any BTC at all you can spend it all to find out these points for yourself. And if you don't, all the same, you can spend your time reading up on the history of Bitcoin, for about the same results. In either case...good luck.