hi
well there are good and bad DSL providers. it all depends on areas. you will have to ask people from your area who have DSL as to how it works etc.. no one can tell better than them.
the prices go around 50-60 bucks a month(most of the time the prices are according to the down/up speed you want). and you should check out for offers coz most of them now provide modem and all necessary hardware for free and free installations etc.. you will have to check out the current offers in your areas.
one big thing to consider before gettign a DSL is checking how far the office/control center of that DSL provider in your ares is from your house.
DSL only works effectively upto a certain amount of distance after that it's quality degrades.
below are some websites where you can find more informations and check availability, prices etc...
http://www.cnet.com/internet/0-3762.html?tag=dir
well the above link will provide you with loads of info on everything.
hope it helps. feel free to ask anythying you want.