i believe there are legal issues with accessing someone else's wireless connection without their permission.
question 1:
yes, if you have a wireless card/built in wireless on your cpu or laptop, you can check to see if any wirless connections are available. ex. wifi spots can be free.
Just make a connection on your psp, and scan to find the connection you want to use. Just make it all easy settings and viola you are using a wireless router, although to let you know, it's illigal to use other peoples internet without permission. So, just ask the people with the connection.