I will address the second part of the question first. Only YOU can let people stop you. People can be jealous and unprofessional and therefore not help you. In that case you need to meet new people who will.
Also, no one else can make your work look low quality, right? You are the photographer, therefore you are deciding the equipment you use, your lighting, and making all of the decisions that produce your finished work that you put in your portfolio.
Now to address the first part of the question: How do you get your portfolio to the right people? Depending on the industry of photography you're in, you'd be targeting different people. Movie and TV set still photographers, target studio photo editors.
1. Find out who judges the portfolios in the area of photography you're in
2. Contact their office to find out their submission policy and what format they want the portfolio in
3. If they don't accept unsolicited materials, ask who they accept materials from (reps, agents)
4. Contact those reps and agents
5. If after all of this, you still can't get your work seen, let me know and I'll start from the basics about creating relationships and getting referrals
For more tips and articles by top entertainment industry coach, The Greenlight Coach, visit www.TheGreenlightCoachBlog.com