Find your local homebrew shop and stop in. They have starter kits that have everything you need to begin brewing. Most starter kits won't come with a kettle, so the shop will recommend you pick one up along with the kit, but in reality, if you're on a tight budget, you could get by for a short time with a large kettle from home. But it would be one of the first additions you should make to your system. The best thing to do is wait until you can buy a big enough one for full boils. Partial boils are fine for beginners, that's how I started. But if you're going to spend money on a kettle, just get one big enough for full boils and be done with it; you're beer will be better for it. Anything else that doesn't come in the kit are just things that come in time as you invest in the hobby. Some are essential to making better beer and other things just make your day easier and more consistent.
If you don't have a homebrew shop near you, check out morebeer.com and find their starter kits. The site is super easy to navigate and they have everything you need for a quick start or a full system. Good luck! Let us know how you do! Oh, and pick up John Palmer's How to Brew, wherever you do your shopping. Read it. Study it. Live it.