It is bewildering to me to think that you want to build a PCB when you don't even know what parts you need since you haven't really "tried" experimenting yet.
PLEASE. Invest in some generic parts as was mentioned above... PLEASE. Read the PLAYGROUND articles to help you figure out what you want to do.
BUY a prototyping board and some wires... play play and play some more and get a FINAL design built and working and only AFTER that should you think about a PCB.
I've been making my own PCB's for 30 years and I still make mistakes... I would hate to think I do that with a project I sent to a PCB shop to have made.
Again... if you don't really know what you are doing... start at the beginning and learn. I know it takes time... but that's what you need to do.