My advice to you would to be start playing in the smaller games like 2v2's and 3v3's. Rarely do people get booted from these and the skill/competition level is lower as well. I sometimes see the same "less skilled" people join big games again and again, and wonder what they are getting out of being constantly rushed off the face of the earth.
While I don't agree with booting anyone but smurfs and people who go AFK, if you are constantly getting booted maybe you need to take a step back and ask yourself if there is a better decision you can make as an individual.
There is also nothing wrong with asking in the chat lobby if someone who has been playing longer can help you. I help new players all the time in games against the computer.
And if all else fails, make an name like Army of Scouts, Noob Hammer, Marza Rush2u, etc. Win 3 games on a super small map with an easy comp, make a game then leave it (having a 4 games, 3 wins record) and pretend to be a smurf.