You can add a kiosk to any community lot yourself. In Build/Buy Mode on a community lot, look under Electronics > Miscellaneous . How to Purchase Travel to a community lot that has the blue kiosk. Click the kiosk and select "Buy... > Cell Phone" .
Most premade community lots, like the Student Union, already have one. sims 2 where to buy cell phone
If you have the Nightlife expansion, kiosks are often located at lots like Fresh Rush Grocery or Cold Issue Clothing . You can add a kiosk to any community lot yourself