I need some help see i got a sigil stone and i found a oblivion circle like thing and it has a skull were i put the sigil stone and i need some sort of offering can you help me out on how to do this please.

read the book on the table next to it.

Yeah it's the Atronach forge. Look up recipes or find them in game.

heres a link to all the recipes if you want to know them all
http://elderscrolls.wikia.com/wiki/Atronach_Forge