Upgrading your wireless or adding a wireless to a notebook is pretty foolproof. You just have to make sure that the card you buy fits into the socket that is in your laptop. Most laptops have a hatch that you can open from underneath it to add and remove things like RAM and miniPCI cards. Do you have a specific question or you just unsure if you should venture into this endeavor solo?

*edit*

Didn't scroll down that far to read your question. What I recommend doing is contacting HP via email with 'will "x card" fit into "y slot."'