A good question to ask is "What's your budget?" This will give the brewing gurus here a better idea of what to get first as far as necessities vs luxuries go.
IMO, I think you could probably piece together a good equipment setup if you're willing to take the time to put it all together. At the same time, kits from Midwest, Northern Brewer, etc. give you the basic items to get you going with out having to do a lot of hunting and scavenging of individual pieces. All you would have to do is add the other things like the kettle, bottles, and other items.
Another option to think about if you're on a small budget is a smaller scaled equipment setup. Northern Brewer offers 1 gallon kits and places like Brooklyn Brewshop and Small Batch Homebrew are exclusive to the small batch brewer. The good things about small batch brewing is the price, plus you can have some variety (ex: five different one gallon bottled brew vs the same amount of bottles for one 5 gallon flavor). Another advantage, price wise, is things like a stand alone burner (plus the propane tank if you don't have one) and immersion chillers aren't really needed.
Another thing with small batch brew is you'll "have" to brew more often since these aren't typical 5 gallon recipes. That's good as the more you brew, the more experience you'll have. Hope this helps.