Numi -
The point here is not to learn how practioners do financial modeling in their day to day life. No two firms are going to use the exact same financial modeling techniques. All of them (no matter if they have an in-house person or whether they buy their models from an external firm) place their own spin on things.
The objective of someone who is getting started (or is still in school) should be to learn to understand the principles behind how financial models are built. That’s what the Wiley Finance, Bloomberg, Damodaran, etc. do, and that’s what they’re supposed to do. If you want specific book titles, look at the CFA curriculum textbooks and any intro to corporate finance class website. If you still can’t understand something like DCF after reading Ross/Westerfield, Damodaran, or Brealy/Myers, etc. you’re not trying at all or have some learning disability.
Things are always going to change and evolve, and nobody is going to stop learning new things once they leave school. It’s a hell of a lot easier to grasp new twists on models when you actually have a solid understanding of the basic founding principles. If you don’t understand the basics, you’ll always be grasping at straws trying to keep up every single time something “new” comes along and/or you change employers.
And speaking of employers, the vast majority of firms train their hires so that they have some assurance that the person they hired knows what they’re doing and is throurougly familiar with the rules of the firm. You can’t seriously expect people to believe that they’ll let a new hire have access to client data/funds without so much as an orientation of what is acceptable and what isn’t.
Taking one of these “break into the biz” courses offered by anonymous hucksters is a waste of money. If the person behind the “course” really does work (or worked) in the biz, they’re legally prohibited from divulging any of the real models they use at work. Goldman Sach’s (and others) successfully prosecuted a programmer who stole some code a while back. So it’s not like you can get away with selling propietary firm models on the side without your firm noticing and suing your ass.
So what you’re getting for your $600 (or however much they cost) course in super secret real life financial modeling is a textbook explanation of DCF. You can understand that from your college textbooks and free on-line tutorials. With Coursera, MIT Open Courses, London Open University, Khan Academy and many many other free websites, there’s no way that you’re not going to understand the concepts. Whatever “real life” knowledge you need to do your day to day tasks will be taught to you in the training sessions. You look like a fool if you’re so silly as to divulge on your resume / interview that you took one of these break into the biz courses to learn financial modeling.
I don’t think all such companies are run by scumbags, though. Some of them are useful in the sense that they explain the industry to people that don’t know about it at all. It’s immensly useful to know all the different kinds of firms, what they do and what they look for in entry level applicants, how to structure your resume, etc.