"a) How big of a drop should I look at?"
That depends... are you concerned about maintaining decent ride quality?
"b) What kind and who sells them?"
- Eibach (www.eibach.com) - 1" drop all around
- H&R (www.hrsprings.com) - 1.4" drop front / 1.3" drop rear
- there are many others with a bigger drop, I'll let someone else describe those
"What should I look to spend and where is the best place to look for them? Im looking for anywhere froma 1.5-2.0" drop."
Most of the springs can be purchased for under $225. It seems like some of the other springs out there that drop more than 1.5" tend to have issues -- uneven stance, bouncy feel, etc. Except for the Apex springs, and last I heard they aren't available here in the US anymore. You might look at B&G and H&R though, I think they're probably both decent springs. H&R seems to be a little better known for their quality, however.