Okay, you can't really "find" a demon in relevance to the paranormal. One finds YOU.
Wikipedia has a very long list of theological demon names. The website also has a page dedicated to a general list of demon names. Another website one can find demon names is Gods and Monsters.
In the Demon headmaster i know that the setting for series one is in a school i hope this helps :-)
On the internet or you can buy the book!
Dean and Sam did find out about John Winchester's deal with the demon to save Dean in season four.
behind the oakfield demon door.
you cant get it, you must combine to get it. to get it combine a bitterbug with honey to make a catalyst. combine the catalyst with a might seed to get the DEMON DRUG. but after that you can get a mega demon drug by combining the DEMON DRUG with a pale extract(found from giginox) to make a mega demon drug, combine the mega demon drug with a monster bone M to make a demon horn, which makes whoever hears it gain a mega attack boost.
Finish the quest "Demon Slayer
Lesser demon: 85 Greater demon: 97 Revenant demon: 150-250 Black demon: 167 Abyssal demon: 87
According to this site about Satanism, the demons Seere and Vual can control time.If you are interested in this you may find the above mentioned website compelling.
Rahab - the demon of Pride Mammon - the demon of Greed Maggenti - the demon of Gluttony Andrealphus - the demon of Lust Asmodeus - the demon of Wrath Laviathen - the demon of Envy & Belphegor the demon of Sloth
Rocks containing Tin can be found south east of Varrock or directly east of the wizards circle where you fight the demon in the "Demon Slayer" quest.
Take part in the 7 demon lord quest. The final demon lord is in destroyed belt and you'll be given access to it.