conneted users
 

some1 tell me the command for knowing the ip of a person connected to my computer

who
or
who -u

will tell you who's logged on. If coming in through the network, it'll list the hostname. Has a lot or other useful options, too.

It has some interesting quirks, such as substituting "-m" [ show only yourself ] whenever TWO parameters are given, this leads to the most-known use "who am i" or "who is great" (both the same as who -m).

mlp

If you meant to know what are the active connections you can use:

netstat