To get a land line, simply contact Chunghua Telecom (中華電信) at their 24-hour service number (123) and follow their intructions.

There are many cell phone service providers in Taichung.  The rates are often very similar
unless you have several friends using the same service.  Then it makes sense to get the same
service provider that they have as you will get discounted rates for calling on the same
network.  Unlike America, the cost of the call is billed to the caller only.  It does not
cost you anything to recieve a phone call.  Taiwan Mobile and Chunghua Telecom both offer English services. 

If you have a friend who has an old cell phone around (almost everyone does) you can
use their phone and get a what is called an "IF" card from 7-11 or any other convenience
store.  The difference between this and getting your own service is that it is more
temporary.  All the cards are prepaid and therefore you dont have to enter into a two year
contract which is normally required.

If you know you will be staying in Taiwan for at least two years, it makes sense to apply for your own number.  The calling charges are significantly cheaper and you can get a new phone for quite a bit cheaper if you buy it with a plan.

What you will need to apply:
1.  Your passport
2.  Your ARC
3.  In some cases, a cosigner (depending on which company you apply with)

Taiwan Mobile:
TWM users can dial the toll-free short code 85238 to receive a text message containing our nearest service location
24-hour English toll-free customer hotline:
In Taiwan: Dial 188 or 02-6606-2977
Overseas: +886-2-6606-2999 then press 7
Taiwan Mobile English Website

Chunghua Telecom.
Chunghua Telecom English Site
or call Chunghua Telecom (中華電信) at 123.