First of all, I know nothing about networks. Some people in my apartment building are going to pay to use our internet. We have charter that comes in through coaxial, into a modem and into a wireless router (that also has four ethernet outputs on the back). I would like to be able to see who is accessing the wifi, at least get an ip address. And also, could anyone view what we surf in our apartment if we're using the wired ports on the router?

Not if you use the wired ports, probably not.

You can view who's on by IP by looking at the router's DHCP logs.

Can't you also use a wireless network analyzer to see MAC addresses associated with the AP?

I don't know how to view the DHCP. I can't even find the administrative tools to activate it or whatever.

Log into your router by (usually) typing in the IP address in a browser. If you don't know what the IP address is and you're on a windows xp box, you can:
Start -> Run and type 'cmd'

and type

ipconfig

to look up the gateway. (it's usually 192.168.1.1, 192.168.0.1 or something like that, but it could be different depending on your router)

Most wireless routers have a web control panel, and the DHCP listings are usually in somewhere labeled 'local network' or something.

What wireless router do you have?

it's a netgear

i did what you said, and it asked for a username and password. i entered the username and password to my network, but it didn't work. do i need some manufacturer bullshit here?

Typically the default login is something like admin:admin, adminassword, admin:<blank>, <blank>assword, etc.

You can look up your model here

Often it's written on the router. And IP addresses by themselves won't help, you need the MAC addresses of computers accessing your network.

I have a similar problem on my wireless internet, I have an unsecured network, and I need to collect money from the whores who use it. I'm going to be nice, if that doesn't work I'm going to MAC deny, if that doesn't work I'll switch to a MAC allow system.

You can ping sweep the LAN too. With NMAP you can get info on what OS's they're running too.