Welcome to DDO! Have you been by the
DDO Wiki ? That and the
Character Planner are perhaps the premier tools for building your character.
Note that most forum builds are focused on endgame raids and epic quests, and might not be accessible in terms of gear/tomes/account options. I would highly recommend Tihocan's
Revised Paths which take the concepts used for the pregenerated builds offered at character creation and optimises them for accessibility/viability.
Perhaps the biggest distinctions in DDO from D&D/other D&D games:
Spellpoints - rather than spells per day, spellcasting classes have mana pools.
Enhancements - these can be reset every 3 days for a nominal fee
Real-time rather than turn-based - you can dodge many spells/attacks/traps with quick enough keyboard reflexes.
Also, there is a tendency towards min/maxing, although Constitution is highly revered and not a 'dump stat'.
Toughness is *extremely* valuable in DDO, by offering additional Enhancements for more HP. Almost every character takes Toughness in DDO.