Welcome to hairloss hell!
Since your new to hairloss and probably still have a good head of hair the smartest regimen for you my friend would be proscar and Nizoral shampoo followed a conditioner as it dries the hair.
That there regimen is a solid one. Cheap and easy to live with. Minoxidil is a good product but your best keeping off it for now, unless you want to be tied to using 2x a day forever.
With proscar you have a 83% chance of maintaining what you have, and as for regrowth, who knows, there are three possibilties, no regrowth, moderate regrowth, good regrowth - Which category you fall under is a mystery intil a few months down the road.
As for 'how long can you expect results' that's very subjective, read this board and you will find people that have no success with proscar, and others anywhere from 2 - 10 years... which is about as long as the drug has been used for.