Hi there Whipple. You are in the right place. I have made tremendous strides in getting into some really great Libraries/Catalogs here. A few pointers/things to take note of..
1) Know what you want, and set a plan for achieving it. Do you want to primarily have residual back-end royalties, do you want to compose/write for Royalty Free, do you need upfront monies, are you looking at mainly Film Supervisors, etc..
2) Read ALL of the Library Ratings and Reviews!! There is great information in them, and some really honest candor!!
3) Watch the conversations that happen inside the Forum Topics. You will get a LOT of great information there, and get to see some solid information from real industry veterans!!
I wish you all the best, and to you all much success!!
(side-note) One of the big “peeves” here is newer people asking a lot of questions about how to get “from 0-to-100 in one second”. To my knowledge, there simply is no fast-track, or “known” set way to earn 6 figures just by joining forums. This is a “Long-Haul business” where setting a course, and building placements/track-record WILL get you into bigger Libraries. Lots of work and preparation seem to be the key!!