How do i connect my ps3 to the internet if i dont have wifi?

Your PS3 supports both wired and wireless. Heres how I have mine set up, Ive been running wired since day 1. 1st- hook your ps3 up to your modem or router with an ethernet cable. {im assuming ps3 is plugged into the tv, if not hook it up}
2- go in to your network setting on ps3.. If you start at the far left go over click and all the way down. You will see network settings. click on it and go down to the 3rd option there.. Internet connection settings. You will get a pop up that says your ps3 will be disconnected from the internet if you proceed, just hit ok. It usually automatically detects if you have the ethernet cable plugged in but just in case it doesnt go ahead and select wired. after that, just select auto for everything else. You will go through about 5 questions and it will be ready to do an internet connection test. All should be well.
If that doesnt work, make sure all the cables are plugged in and try again.If you are able to connect to the internet after that but get booted off, go back into network settings again and disable the media server. Hope that helps.. Happy Gaming

What internet connection do you have as in what modem it is just a case of plugging an ethernet cable into the rear of the ps3 and from the back of your modem let me know in more detail of your problem