Don's Passman's book is fantastic! I am so glad you mentioned it. In fact he just published his 9th addition which can be purchased here: https://www.amazon.com/Need-Know-About-Music-Business/dp/1501104896/ref=dp_ob_title_bk
As for your situation. My best advice is don't give up, get creative. The demand for music supervision services is growing and as we lay out in our book it's across all professional fields. For example I have a colleague who has made a modest but profitable business music supervising for internal corporate videos. Boring yes. A real business. Yes. She was crafty enough to figure out the niche and exploit it. Now the video producers who make these corporate reels go to her. So don't give up. Ramsay
Apple Loops - royalty free I'm pretty sure.
If you sample a song, it depends (sort of). You technically should credit and clear all samples with whoever owns the master (thus owing them royalties and owing royalties to whoever owns the publishing rights for any performance of it I believe), but if you sample and process a snare or something, saying you stole it is going to be a pretty difficult case to make (assuming anyone even notices).
That being said, if you were to make a bootleg remix of a song or take a lead vocal/melody and put it on the internet - there's a good chance someone/an automated system might notice and it could get taken down. The chances of getting sued however are extremely slim in the case of the making a freely available remix or track containing samples from commercial music. I'm no legal expert, but from I've watched and read, basically if the record companies care enough to sue you for this, that means you should celebrate because you've already made it big.
If you're distributing copies commercially (thus generating revenue) where the sample is obvious, however, legal action is probably more likely and less cause for celebration. If you want to learn more, https://www.amazon.com/Need-Know-About-Music-Business/dp/1501104896 is a fantastic resource for all the relevant details.
All this being said, if you are just making songs for practice or to play live in a DJ set, I wouldn't think twice about sampling something - just go for it. If you're worried something might be so good you want to release it, trust that it's worth clearing the sample or that you're creative enough to replace it with something else (EDM producers will do this often with bootleg remixes that do better than they expected in their live sets).
PSA: Anyone who wants to do anything serious regarding music production or anything involving the music industry for that matter may as well just go and read this book before asking any other questions as it will probably answer all of the ones you have.
That, and it's just an interesting book by itself. Passman is a great writer with a sense of humor and keeps you entertained.
To the OP: Read the book. It has the answer to your question and explains it better than anyone on reddit, including myself, would be able to.
You're asking some good questions.
If you are trying to pitch your songs for other artists to record and perform you should be seeking a publishing deal. They will represent your catalog through their existng relationships to A&R reps and producers and occasionally directly to other artists.
Contracts - speak with a music attorney
Copyrights - if you are trying to sell the song a simple voice guitar demo is sufficient, if you are trying to sell or license your master recording you will need to copyright the audio recording as well. In the U.S. this can be done simultaneously. You should also register them with the PROs for each contributing writer as well as Soundexchange to be sure you collect all royalties due from broadcast, streaming etc.
An agent will book tours for you and receive a percentage of that revenue as payment. A songpusher will rep your tracks to music supervisors and again will receive a percentage of the money received for the placement. Do not pay any one upfront for either of these things.
The ISA will accept you as a member after one of your songs has been recorded and released commercially by a label or placed in TV or film. Wait until you qualify before considering joining.
Songbay, Taxi, Music X-Ray etc. Never pay anyone a fee upfront to rep your act or music.
Streaming, somewhere around 20% of the songs on Spotify have NEVER been listened to. Don't count on revenue from streaming unless you have momentum from radio play, touring etc. otherwise you may fall into that 20%.
Asking "what am I not asking?" is always smart. One thing to consider is reading Don Passman's book it's dry and at time downright boring but you'll have a much deeper understanding of how the music industry moves.
Edit: spelling
A quick google search gives fell well rated books such as this one
However world is changing rapidly and the music business is no exception. Physical sales are low and streams are not good income sources. More artists are franchising, making royalties from not only their sound but also their face. Maybe there are newer books but imo advice on youtube is much more useful. just one example bout social platform promotion
All You Need to Know About the Music Business
https://www.amazon.com/gp/product/1501104896/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Almost. Read Don Passman's Book
You have the grand total of what I know about stock music. I can give you advice about most else but I didn't learn anything about stock music until i was already out of the game and even then, not much. If you don't have it already, get this book by Donald Passman. Seems like a scam but it's really a great resource. a couple kids, some talent and instruments plus this book can be a pretty formidable force in the world. I don't remember him doing much on stock music though but I could have glossed over it in my young and zealous days.
My other key advice I give everyone (and I'm probably repeating myself - for good reason) is to meet people doing this. Nothing scummy, just network and make friends. You don't have to be all businessy right away. It's better if you establish real relationships with some folks. Plenty of time for less casual relationships later. Just keep in mind that these cats will be auditioning for a lot of the same work you are so keep the salt handy when the advice comes in. A lot of it will be genuine and helpful and in your interest but every now and then some sabotage (usually unintentional) will slip in there. Any big move needs to be bounced off musician friends AND non-musician friends just for balance. Usually exposes the bad advice.
I did a little research. I don't know this guy but this blog post seems relevant. He started out with no experience in commercial music and seems to have had more success than he anticipated. Lots of links and real world experience. Can't imagine you'll get a bigger boost than this at this stage. Hopefully some of the other commenters with experience can boost you too.
Good luck and can't wait to hear your work in a really great movie someday.
Don Passman's Book is a great place to start. It may also give you some good insight into the legal side of things.
THIS BOOKLET is geared toward the UK but also has some good basic info that applies in any country.
That's not what's happening.
But there's not nearly enough room in a reddit comment to thoroughly explain how the music industry works.
If you're really interested, I'd suggest Donald Passman's book <em>All You Need to Know About the Music Business</em>. He's a music industry attorney and a really funny guy; it's a great read that gets as detailed or as abridged as you want depending on how you read it.