Finding contacts in the music industry is a very difficult thing to do if you are looking to make a name for yourself for your music. Most people who will be able to help you will not be keen to speak to you in the first place and it will normally be best to simply play anywhere you can in a bid to get spotted by somebody who has some power.
Another good way of making waves is to network hard and network often to build your list of contacts. In the music industry you never know who will know somebody who can help you. Work with other bands and promoters to help with getting your music heard and take every opportunity you are ever offered as you never know where you might be spotted.
Finding contacts for musicians and bands is much easier now on the internet but there used to be plenty of offline sources too.
The music industry is a very tight knit community but contacts are great to have to give you access to all you need.