Regarding number 2, that is a very wise piece of advice. By simply waiting you can either determine whether you need the item or not and also keep tabs on prices. The company I work for is Wishabi and we will notify you if any of the items on your wishlist drop in price or if a really good deal is found for it. So that 30 day waiting period is a great way to save money. We've seen items like flatscreen TV's drop like crazy over the past couple of weeks.
And on number 3, retailmenot is a great site to check out if you're planning on buying anything. Checking sites like that can save a lot of money in the long run.
I find it difficult now to buy items that aren't marked down or have some sort of promotion attached to them. Maybe we're spoiled a bit as consumers, or maybe we're just more savvy than ever before.