How much does wifi cost?

Wifi can refer to your own home wireless network or to wireless access provided by a third party. Which are you referring to?

Depends on where you get it from and the level of service.

Generally, WiFi requires a broadband Internet Service Provider and a wireless router. The ISP provider generally costs $25-$50/month. The router costs $40 to over $100 as a one time purchase. You also need a wireless network adapter in the PC.

There are also public WiFi networks that you can connect to with a woreless adapter in you're a PC. Some charge a small fee for a connection. Some may be free.

Free if you find a Starbucks or McDonalds giving it to customers. Some cities are providing it to all residents by placing wireless routers is various parts of their town. If you don't have this access you can get a DSL line from ATT for a about $30 if you already have them for phone service. DISH and others can also set you up as well as many local providers for around $60 a month.