Still waiting for an xbla version of the walkthrough, though apart from the button configuration there should be no difference from the Playstation walkthroughs below (given that the game remains faithful to the original). If you do happen to find an Xbox live Arcade version, please post the link in the comments section and i'll get right on it.
Castlevania SOTN Walkthrough from Gamefaq
Casltevania Fan Gallery (artbooks, scans)
Castlevania Bestiary from 1up
Maps from rpg classics (spoilers)
Walkthrough list from Neoseeker
Walkthrough scans and secrets from gamespy
Clickable inkies Castlevania SOTN Symphony of the night arcade xbox live arcade xbla xbox 360 walkthrough walk through walk thru tips cheats hints secrets