Lots of people have success in keeping their hair using a combination of Nizoral, Finasteride (Proscar cut in 1/4s is cheapest), and 5% Minoxidil. That combo effectively handles DHT and stimulates growth.
I saw some frontal thinning of my own last year in my temples, and I've run that combination (albeit using topical finasteride due to the oral sides) with good success. Takes awhile to recognize the results when it comes to hair loss treatments, however. You should wait at least 6-9 months before giving up on any standard treatment. Patience is key.
I get most of my stuff at
www.genhair.com. Good luck.