Woah...slow down here folks. This is a first-timer. Starting off with $600 is not necessary. Not even in the ballpark. You want to go cheap, cheap, cheap. This is bbq, the sweet science of turning the lowest food, with the poorest equipment, into the most desired.
I recommend doing this. Get on Craigslist and find a kettle (preferably Weber) and a smoker that looks like (or is) a Weber Smoky Mountain. Then stop. That is all you need to get you started and I would go with the cheapest you can find, and this is why.
First, you may not enjoy this vice as much as another. (I know brethren...blasphemy! blasphemy!). $600 is a lot of fun on something else.
Second, if you can consistently put out quality food on these two cookers, you will be successful on just about anything.
Third, once you reach that consistent quality you are going to be hooked and that is when the hobby turns into a vice. You are going to want to give these away to a buddy (or keep them in your arsenal, I have given away my original smokers) and upgrade and that is where you start to spend the big money. Seriously...you will start to want to enter competitions and you will dream about a custom smoker that requires a pickup truck to haul.
A used kettle, and a used WSM (or knockoff). Those are the only tools you need to begin. These will be your sensei (Master Splinter). Once you learn from them you can (and will) go bigger.
LG BGE-Brinkman Cimmaron-Custom Pull-behind (old grade school boiler)-Weber Kettle-DCS 30"