To start making some bitcoin visit bitcoin.org and download a bitcoin wallet.
Learn more on bitcoin from weusecoins.com ..
Double click your Bitcoin wallet client and let it sync to the network.
Once your wallet has sync'd you will get an address that will look like
this 1A8kgTvz57ATnJ2WhDxQPkmJeAYasqwgWA which you can share with anyone and post online without having to worry about it.
That address is where your coins are stored.
They can be used to buy things or exchange for any currency.
Some ways of getting coins are free (sites / mining) and others will cost you (buying).