Can someone please explain to me the rules about when its appropriate for using ser and estar?

A quick shortcut is to think of estar as temporary and ser as a permanent trait.

Yo estoy enojado: I am angry

Estoy afligido: I am scared

estoy enfermo: I am sick

estoy en casa, en america, en el carro, en la concha de tu madre: Im at home, america, in the car, in your moms pussy, whatever. The point is logically you're not anywhere forever.

Yo soy inteligente:
Yo soy guapo:
Yo soy fuerte:

Now to confuse you a little bit
soy enojado: I am angry?(but I thought anger was temporary!?) Well, if you say "yo soy enojado", it is taken as a permanent character trait. Meaning you are of an angry nature, you're a generally angry person.

Now, women will throw around "estoy gorda" and "soy gorda." The former is feeling kinda bloated, maybe shes was a regular jogger but hasnt gone in a month, or maybe shes been eating a lot this past week. That latter is a fat bitch that is gonna stay that way.

Time is ser.
son las 12

Where will you be tomorrow?
Voy estar en casa

what will your condition be?
voy estar borracho

how do you describe a drunkard?
el es un borracho, siempre jala esa botella.

I find this ambiguity is one of the greatest defect of English language like the one

free = libre = gratis.

ser is permanent.
estar is temporary.

Estoy en la casa. temporary
Soy americano. permanent.


http://www.drlemon.net/grammar/servsestar.html

Also, since you are a spanish speaker, this is a valuable resource: http://users.ipfw.edu/JEHLE/VERBLIST.HTM