I think the best thing you can do to get started is read a lot, and watch some Youtube videos. I recommand that you look at the LTT videos, and especially the TechQuickie if you want to learn the basics about stuff like RAID and other concepts/terms. Then, if you're interested, you can learn more, but at least you'll learn enough to get started and have a basic idea of the concept.
Other than that it's just reading, and experimenting if you can. Look at the topics on this forum, see what builds people propose to other members, it will be slow at first but eventually you'll get more comfortable. It's a slow process, I used to be up to date with hardware and interested in that, but I just stopped coming here and looking at LTT after I got busy with other stuff, I just came back to here and there are a lot of new things to learn ^^