All DS consoles have built-in wi-fi, including the DSi and XL.
If you do not have access to a wireless hotspot, you could get a Nintendo Wi-Fi Adaptor, which acts as one.
Yes, the Nintendo DSi XL has WiFi and can connect to the internet.
You have to own wifi
You Dont.
download it off of DSi ware
The DSi XL is wi-fi enabled if that's what you mean - the 'cost' of wi-fi isn't relevant to the system itself. If a place offers free wi-fi, them yes, the DSi XL can use it. If you've got your own home wireless internet, the XL can use that too if you enter your passcode into it. However it can't magically generate a free signal in places where there is not one.
You can do it on the DSi and DSi XL. If you have internet you can. Use the browser.
Yes all Nintendo DS's no matter what the version have the abilty to receive WIFI.
you have to connect it to the internet
Every single ds, ds lite, dsi, and dsi XL comes with built in wifi. To get to it, you have to have a wifi compatible game, and there will be wifi settings somehwhere on the game. You have to edit the settings. But i cant help you there. :)
You must be in a free-wifi zone, even using DSi/DSi XL you cannot use locked wi-fi point or a Payible one - only Free-wifi zones maybe used
yes a dsi charger fits a dsi XL and a dsi XL fits the dsi
i dont now