I find taking less Adderall or not taking it too late in the day can help. Or trying a different med liek Dexedrine if you can. There are a number of supplements I'd recommend for sleep:
- magnesium (this is not something that always has an immediate noticeable benefit, you may have to take it every night for a while, but it can help with sleep and also helps prevent tolerance to stimulants and other drugs)
- kava
- valerian
- melatonin in small doses: as ErgicMergic said less is more when it comes to melatonin, too much can keep you awake or cause you to wake up in the night or have crazy intense dreams. I find taking a timed-release melatonin to keep you asleep, as well as an instant-release one to get you to sleep fast, to be helpful.
- l-lysine
- l-arginine
- l-ornithine
Sometimes a supplement cocktail works better than just taking one of these things on it's own. I also find that things like having a bedtime routine, an inviting bedroom, no distracting sounds or white noise to mask them, wearing a mask or using black-out curtains, sleep music, a really comfy bed that's the perfect temperature, meditating, and such can help a lot.
Personally I think it's best to try as many behavioural/environmental techniques and natural herbs/supplements as possible before resorting to dependence-causing drugs like benzos.