Xlink Kai is one way of playing over the net, and as ive learned not the only one lol. the thing is with Xlink Kai is that the wireless equipment that you use has to use a certain chipset (the chips inside that make it function) In the case of Xlink Kai it has to be the ZD1211B Chipset. There is information on the teamxlink website about which Wireless Equipment uses this Chipset but i cant find the thread
EDIT:FOUND!
teamxlink.co.uk :: View topic - Compatible Network Cards for PSP and Kai
I use the Datel Wifimax USB Dongle as it was explicitly designed for this purpose, but as i said there is other hardware that is compatible.
This is How:
teamxlink.co.uk :: View topic - Kai's PSP Connection Guide - READ ME FIRST!
And some dude did a vid for youtube:
YouTube - Get your PSP online using Xlink Kai & WiFi Max part 2/3
Unfortunatley, the only game that is played to any great amount is Monster Hunter 2. Thats why i thought the forum would be a good place to play other people and not that damn game you have to spend weeks on.
If you meet the requirements of the hardware. and there are other people that would like to play someone in another country or something, but the game only has ad hoc - Xlink Kai is the answer.
After a few posts on the subject (lol @ psplayer) this fantastic infratructure called Xlink Kai is going to waste IMO.
At the very least check out the website.
XLink Kai: Evolution VII. Global Network Gaming.
I was impressed - then maybe you can consider getting the wifimax. i got mine £25 inc pp from amazon (PS. the software has Access Point mode, which means that your psp can connect to it for the net connection, as if it would for a router)
If you do decide to buy it, its not overtly simple to configure, but i managed it in 20 mins
And yes the service is completely free, just the investment into hardware if you dont have it
If i find the thread for other compatible hardware, ill post it up here
Peace