Ask HN: Does copyright apply to “deals?”

There are numerous websites that share hot deals such as slickdeals and brad's deals. Are the deal sites in any way protected by copyright or can their content be shared freely on my website.

There are also numerous newsletters which provide deals.. can these deals be posted on my website?

I am not against crediting the original website in any way; however, this would be more difficult when the deal is found in a newsletter.

Essentially what I am asking is:

1. what is the minimum attribution required by law when reposting deals

2. what is the best practice?