Yes, the Nintendo DSi XL has WiFi and can connect to the internet.
Indeed-- If you have WiFi with a DSi you can go on the internet.
You have to own wifi
Yes all Nintendo DS's no matter what the version have the abilty to receive WIFI.
No a WiFi router is required.
yes, but you can only have six different wifi locations on it.
Yes you do have to get Internet wifi but possibly there are local liberies or coffee shops that have free wifi.
yes it can =)
Yup. I'm 100% sure. I own a DSi and I gave my friends the wifi connector, because I have a router now. go in the web and check yourself on your ds!!
The Nintendo DSi has a Facebook feature, where when you take a picture, it sends it to your Facebook profile if you have WiFi access.
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. :)
To connect wifi to your Ds you must have a DSi or a Nitendo WIFI USB Connector for about $60.