I hated the sound of the wimpy stock horns so I added a set of Hella Dual Tone Air Horns. Look here for pics:

Hella Dual Tone Air Horn Kit install

 

Again I'm going to post this question again 'cause only one person seems to have tried this:
I ran across a thread last year where someone said that all they did was remove the plastic covering off the stock horns and they sounded infinitely better. Has anyone tried this?

 

I had those exact horns. They are loud, but they weren't deep enough for me.

 

So the sensus is...
You are going to be paying a bit. AND you might as well deck your car out with a compressor and tank that will handle air lockers so you can kill two birds with one stone. I had the higher pitched air horns but my compressor locked up or fried and I have yet to take it apart. Damn... you guys always find something else to add to my want list...