My husband had some insomnia early on in treatment but it has gone away as he's gotten more tired. If you are feeling energetic enough, exercise is a great sleeping aid.
Ambien (zolpiedem) helped me. It works quickly, doesn't give a morning hangover and is pretty cheap as it's available as a generic. I haven't tried the Ambien CR (time released, non-generic). Only thing about ambien is that, for me, I wake up after about 6 hours. But those 6 hours are pretty solid sleep.
Many people have trouble sleeping while on treatment. I tried the Melatonin and it did not work for me so my doctor had to prescribe Ambiem
You may want to try sub lingual Melatonine. I has done wonder for me during treatment and since.