Does anyone sell pre fabricated A pillars with a spot for the tweeters? I really don't feel like fabricating my own and i've never worked with fiberglass.

I haven't seen any pre-fabbed pillars yet, haven't really looked. You should try fiberglassing some. This was copied from the sticky in the interior forum. Check out the sites (I know they describe boxes, but the principle ideas there). I'll be trying to make some soon. When I have them done, I'll post a step by step.

In the mean time....see below.

14. How do I fiberglass my interior?
Well, I'm still learning myself... So, I'm a newbie at that kind of thing and hence am probably a bad source for information, but there are all sorts of places to learn online. http://web.njit.edu/~cas1383/proj/main/ and http://www.fibreglast.com are both really nice sources of information. In short, what you need to do is the following:

1. If you're making a mold for say, a sub box, prep the area with masking tape/aluminum foil. This is absolutely imperative if you're working around areas that you don't want fiberglass everywhere, such as if you're making kick-panels and don't want resin all over your carpet!
2. Pre-cut and layout your mat/cloth in the area you want it.
3. Mix hardening catalyst with fibreglass resin.
4. SATURATE the mat with your resin/hardener mixture. Be sure to remove as many/all of the air bubbles as you work. Air bubbles = create a weak final product.
5. Recoat as necessary. It's not necessary to allow time to dry between layers.
6. Sand. Paint. Admire. Gloat. Brag. Move onto next fibreglass project


Hope this helps, Good Luck!