Matt,
Howdy from down along the coast here in Texas! Good to see another Texan in here!
Gas cookers are all well and good, but you can sure taste the difference in charcoal / wood cooked food! Here is the voice of a lot of years of BBQing on various equipment...
I started off with a Smokey Joe, 14" mini Kettle, whcih is great for apartment living etc... But pretty cramped cooking space, accessories wise. At a minimum I would go with a Jumbo Joe Premium. Which is bottom of the 22" barrel as far as Weber Kettles are concerned. The Original 22" kettle gives you a deeper lower bowl, and the ash sweeper which is nice, but not really super necesary.
I definately recommend for any beyond the Original Premium, adding the hinged cooking grate. That makes adding coals for long cooks so much easier!
Don't write off a Smokey Joe though. You can do an awful lot with them, and they are fantastic for camping grills. (Public park / campground grills are disgusting at best).
I have both a Smokey Joe Silver ($29.00 at Walmart) and a Jumbo Joe Premium ($69.00 Wlalmart Exclusive).
One item that I hightly recommend is that you add a thermometer either a digital probe that feeds out or a mounted regular one, but make sure you get temps just above the cooking grate to know what the food is being exposed to. This allows you to better control the temps. Don't be afraid to drill a hole in the lid to mount a thermometer either!
Once you pass from 2 to 3 people, or if you want to do a batch cook say for a party with friends, or just cooking up a mess of BBQ / Grilling on Sunday to microwave for meals through the week, you will hate the space liminations of the 14 and 18" grills... The 22 really becomes your friend fast!
The shutters both on both on bottom, and on top should be used in conjunction with each other to regulate air flow, thus regulating temps.
Use a Charcoal chimney starter. Lighter fluid is for amateurs that want their food to taste like an oil well. As of late, almost everywhere I have seen that sells charcoal sells a chimney. My local HEB grocery store has them in the grilling aisle right with the lighters. They aren't expensive. I think I paid $6.00 for mine. And expect it to get rusty looking fast. They don't stay pretty... Several MFGs sell them. The one I got is labelled Kingsford, and I like it better than the weber one. THe holes make it easier to get a lighter to the paper on bottom...
Lastly, trial and error. Experiment with various charcoals to see what works best for you. Most people seem to prefer Royal Oak, or Kingsford in the Blue bag. I like Kingsford Mesquite, but will sometimes use blue bag and toss in some chunks of pecan for the smoke. Find out what works best for you, and what you prefer...
Welcome to the world of barbecuing on coals! The way it should be!