I would like to know how to edit the creatures speed, size, health, etc. Anyone know where I can find a tutorial mainly on creatures?

It's pretty self explanatory when you open the animal's tab in the CK.

Ok how about spawning?

I hate it when people do what I did, reply with "oh, it's easy" and not give at least a clue.
Ok, from the beginning:
I'll use Shadowmere as an example.

On the Object Window:
* Actor > Actor > Horserace
A note: the horse templates (the models used to base all the other horses in game) their editor IDs start with "enc"
Any change you make to a template will affect all the other horses based on that template. You can tell which template is used for that particular horse by double-clicking on the editor ID, and looking at the bottom left under Template Data. You can see here that you can choose different aspects of that template to further customize the creature. Shadowmere is not associated with any templates, so any changes you make to it apply only to Shadowmere.

* Double click on Shadowmere.
The Actor window opens. On the left under the ID and name, you see a series of tick boxes where you see different options for handling the character. Shadowmere is set to respawn, which means it will die, but then come back to life. If you were to click essential, then the behavior would be like those Imperial generals who take damage but don't die. Protected, no damage, no death.

* Click on the stats tab.
Here you can change level, health, speed, stamina, skills, etc.

Note on spawning: Shadowmere respawns rather quickly, and so do the characters on which you click the respawn option within the actor's tab. If you want to alter respawning times in game, as in how long it takes for a vendor to respawn inventory, or a cell to respawn enemies, you need to go to the Menu bar, under Gameplay > Settings. Enter spawn in the filter (you'll see 4 options) and change the numeric value for the spawn time you want to alter.

Now thats what I'm talking about systemshock! How about leveled list for creatures? How do I make one, what is it?

For actors (NPCs, animals, monsters, etc):
Actors > LeveledCharacter. Right click on the left, select new. You can either drag and drop actors from the list, or right-click and select new. Selecting new will place the very first actor found on the list, but you can highlight it, then select the right actor with the Object drop down on the right. Easier to just drag and drop. I don't know what the limit of actors is, but 5-7 should suffice. You then can choose the level the actor is going to spawn and how many spawn for each actor on the list. The actual level of the actor, that is set in the Actor's window.
Once you are done with it, give it a new ID editor, and then you can drag an d drop it into the render window. You should see an icon (an M with something like an arrow sticking out) instead of the creature

For armor/clothing/weapons:
Items > leveledItem
Same principle as above. Drop it in containers, user inventories..

Ok so what does doing what you said do for me in layman terms?

A leveled list is a list of items or creatures that are going to pop up in your game when your character reaches a certain level. This aids in maintaining a somewhat consistent level of balance in the game as your character levels up.

For example: Say you are making a dungeon. You add a whole bunch of skeevers in it. If the player is at level 1 and enters the dungeon with a dagger, the player is in for a fight. If the player enters same the dungeon at level 35 wearing glass armor and wielding an ebony axe, the player wouldn't even have to fight going through the dungeon, because the skeevers are not going to be able to make much damage. heck, you could even wear the ebony mail and kill them all without landing a blow

So, how do you prevent that? With a leveled list. Rather than just adding skeevers to your dungeon, you create a leveled list with as many creatures as you think is necessary, and assign them the level in which they are going to appear. So, following the dungeon example, you could create a LeveledCharacter list with the following:

1 skeever
5 wolf
10 bandit
15 bear
20 spriggan

What does that mean? It means that if the player enters the dungeon while at level 1 but at less than 5, the player is going to face a skeever. If the player enters the dungeon at level 5 but less than 10, the player is going to face a wolf. If the player enters the dungeon at level 10 but less than 15, the player is going to face a bandit... and so on.

The same logic applies to item lists: you usually don't want the player to open a chest and find ebony armor and weapons at level 1 and make the game a cakewalk, nor face an enemy wearing ebony armor and wielding an enchanted ebony sword when you are level 1.

Ok so how do I determine how strong the enemy is? Do I change the level of the individual enemy or do I manually change the stats of the enemy? For example, suppose I choose a bandit for level 1 and another bandit for level 10, how do I make the bandit stronger since its technically the same thing?

Would like to know how to make creatures more powerful.

You make creatures more powerful in each creature's Actor window.

So, for example, you can go to Actors > Actor, open EncBandit00Template, give it a base health offset of 100000, one-handed of 1000, and put it in your leveledCharacter list as spawning when the player is at level 1.

Base health offset of 10000? Does that mean his hp is 10000? And if I edit one actor will it effect other? For example if I wanted to make a male sabrecat more powerful than the female if I change the male stats will it change the females too?

Also there are like 6 versions of each creature, whats the difference between them?

The 100000 and 1000 are just numbers I used as examples. When you input the offsets, you'll see the stats change in the grayed out boxes, which reflect the actual health, stamina, etc of the NPC in game.

Editing one actor can affect another, if you edit a base or template actor. The names of base actors normally start with "enc". If you change any "enc" actor, and another actor is based on that "enc", it can affect it if the attribute is inherited, as determined by the Template Data in the second actor's window: remember that you can base one actor on another, but you can further customize the other by selecting only those attributes you want the actor to inherit. So, following your sabre cat example, you can create a new actor, then on the actor's window under template data select ActorBase as encSabreCat, then tick every inheritance option under it, then de-select traits and stats, then edit the traits and stats of your new model.
You want to select traits and stats first so the fields in the new model get filled in with the base actor's stats, then when you de-select them, you are able to edit them.

Hi, do you know the creation kit has a website that explains all of what your asking?

Hi, I've been there, but what happens if I had a question for something? The wiki only has what it has. But I cant actually go back and forth with it and ask questions outside of whats there. This thread will not only help me, but others that are interested in making creatures or manipulating creatures too. Thanks for the suggestion though.

Ok thanks that helped a lot with making a new variation. So how do I give this new actor a texture? I want it to look different too.

Also is base health the level 1 health? And the offset is with every level up it gets the offset added onto the base? So If the base is 100hp and offset is 200 then at level one the player will encounter a sabrecat with 100hp at level 2 it will be 300hp and so on? Is that correct? If so what happens if they are unleveled?