Hi,
You don't need to use the registry etc. things like browser and IP are done through cookies and/or sessions. The most popular ones are in PHP such as:
REMOTE ADDR
HTTP USER AGENT
REMOTE HOST
These are just some variables used to retrieve the values, then you can document.write or echo them where ever you want them to show on your page.
I have attached a sample which was knocked together for someone who wanted to be emailed every time a user went to a specific page.(new visitors etc).
Have a look at the code and play with. If you want the email change it to your email address and see the output.
Do a search on google on the above and look at the code.
Good Luck.
Andy