I can't say I'm a huge do-it-yourselfer, but when I have a project I need supplies for I head over to Home Depot. The place is absolutely huge and has everything that you could ever want. I've gone in quite a few times with no idea what isle to locate the items on my list, and there's always a store associate who ready and willing to help guide me.
Hate the idea of navigating through their huge isles? You can always shop online and pick it up at the store. I've opted for this a few times when I know my trip will send me throughout the store and I'm in a bit of a time crunch, or just feeling lazy. These transactions have always been quick and easy.
For any project you may have, I'd suggest going to Home Depot to get your supplies.