So I am completely new to this and I'm not completely sure where to start. I'm looking to build a Dread Necromancer with the Sublime Hellbred race. How do I go about looking up stats for the Sublime Hellbred because I can't find them and how do I fill out the sheet of spells, how do I select equipment, pretty much everything. Any help would be appreciated. 
The Hellbred race is in the Fiendish Codex devoted to Devils. I forget which one that is. How can you be looking to build a "Sublime Hellbred Dread Necromancer" if you don't know where to find things? I believe Dread Necromancer is in Heroes of Horror (I don't have that book) so maybe it also contains the Sublime template as well.
I'm sorry for being blunt but the BEST way to figure out things is to start simple and that generally means using the Player's Handbook. It sounds to me like you want to build an advanced character yet you have no idea how to build ANY character so I suggest starting back at the beginning. You want to drive a racecar in a race without even learning how to drive first.
IIRC Spells for a Dread Necromancer are easy. The class has a list of spells and you know all of the spells on that list. There are some guides to character equipment (I believe Tempest Stormwind has one somewhere in his signature) but it basically is you have X gold that you use to buy Y equipment.
When you are "completely new to this" it is hard to give advise because we have so little to go on especially when it sounds like you want to go from zero to 100 with a snap of your fingers.
StevenO wrote:
Read the players handbook for equipment, skills and feats. Read the heroes of horror book for the dread necro class. Read fiendish codex 2 for the race (unless its some homebrew variant on the race, then read that).
once you've done that, if you still have questions, please come back and tell us what your DM said the starting level, stat generation method, starting gold, and additional house rules there are and we can help out.
Fortunatly for you, a quick google will tell you this is one of the most popular classes, with loads of guides and help.
Ok take it from someone whose favorite class is the Dread Necromancer. There are few things you'll need. Since you're new, i'd take everyone's adviceand start small by using the players handbook when it comes to feats and skills before branching out to more advaced techniques. Since the dread necro is from a different book, they also use a few different spells from that book, so read them and make sure between you and your dm that spell components are valid as well that you understand what the spell is capable of.
Now since we got that out of the way lets talk about what you need...
1) CHARISMA!!! A dread necro needs his charisma for damn near everything about his class, so the higher the stat, the better he is. Depending on rolls and what your looking for dex and con are you next highest and the rest are dump stats.
2) focus on your spells and spell like abilities using augmented summoning, spell focus and spell penetration for feats
3) since they can wear light armor try and save up for mithral breast plate... It gives you the protection you need and hardly any penalties for magic or skills
If you think you can handle anything else i'd advise also looking into the Libris Mortis books for other interesting feats and possibly prestige classes to help you along the way.