These are some things you should check if you are having problems:
- is PHP enabled on your server? Ask your host...
- are your database connection strings correct? Confirm with your host...
Don't know where your files are?
- use a good FTP app like Transmit or Coda (from Panic) for OSX and Filezilla (crossplatform). It will make a huge difference.
- if you have uploaded and can't find your files or get a not found error message ask your host to show you were your files are (if they won't help you with this then what good are they?).
- free webhosting is not recommended because it often has silly security issues and you will likely experience random problems later.
- personal hosting setups (like on your computer) is not supported - this is an advanced option and you should have an understanding how this works in order to make it happen.