most installers I have ever met were trained by working with someone for a while. Some get certified by SBCA, some dont.
Installing satellite systems isn't all that hard. The experience and training comes in when you have a location with very limited line of site or strange trouble calls.
For example: A customer calls ya and says that every morning when they wake up their system is searching for satellite signal. By midmorning it is working perfectly and continues to work fine all day long. Being able to find the problem and eliminate it without spending an insane amount of time and wasted time driving back to the customers house over and over, is what it means to be a real installer.
By the way, in that particular instance it was a bad connection outside at the groundblock. Connectors were getting water in them because of the dew at night, by mid morning(after it had warmed up) and the water had evaporated and the problem went a way.
One of my new installers went back to that particular house 4 different days before I went over and looked at it myself. He re-aligned the dish once. Swapped out the reciever once, swapped out the lnb twice.
Installing is not hard, just takes some common sense and knowledge of basic construction and electrical systems.
Best way to get into it would to see if any local companys are willing to hire you part-time.
