UNIX for Dummies Questions & Answers

Hi guys,
I'm new to the forum so I apologize if this is in the wrong section.
I'm a senior in high school and I'm interested in getting into systems administration. I've heard the best way to get into systems administration is to volunteer at a company to help out the SA's so you can get hands on experience. Almost like an apprenticeship. Then to take the certification test and get certified. I'd like to start out by getting MCSA certified (I know this is a Unix forum but please don't hate me). Here's my questions now... can you guys offer any tips on finding an opportunity to get some hands on experience? I know there's lots of companies that have SA's on staff... but I'm kinda lost on where to start looking. And I also don't know who at the company I would contact about this, the hiring manager? One of the actual SA's at the company? If it helps any I'm in the U.S.
I have some time to think about this because I'm not planning on getting into this until I'm done with high school (end of May).
Again, I know this is a Unix forum... the reason I'm asking here is because you guys seem to be the most knowledgeable from the forums I've seen online
If you guys could give me some advice here, or even give me some tips on things I might not have even thought of I'd appreciate it very much!
Thanks!

Companies that offer Summer Intern programs usually let the schools know. Don't you have a guidance counselor or someone like that at school? Talk to them. Also talk to any teacher who teaches computer science or programming. Warning: there will be few intern positions and many students who want them. Expect competition.

Getting a position as a entry-level desktop support person in a larger company could lead eventually to a SA position. Read some books or websites on producing a resume. Then write a resume and send it off to some companies. Also post it on some resume websites. Call the company and say you are looking for a job and ask who to talk to. Then send the resume to that particular person.

Unfortunately I don't have a guidance counselor because I'm homeschooled