I've posted an overview... not couched in Arduino terms... of working with 1-Wire chips at...
I would heartily second what ril3y said...
You get a lot of of reading the datasheet
... but read the datasheets for several 1-Wire chips... e.g. the DS1820 and, say, the DS2423 (a counter chip... supplies something that I think the Arduino could use!). Gradually you will discover that large parts of each datasheet are repeated in every 1-Wire datasheet, and you will learn what bits you can skim, and what bits are important.