Noob questions with amazon affiliates!

Hello people,

I`m new here and i need some informations if you want and can help me.
1. I want to start amazon affiliate with own website. First time i think to buy an deleted domain with high pagerank or alexa rank ... This can help me ?
2. I`m not decided and not good to keyword research what you think work (reviews, comparations or store)
3. Can help me someone with a niche who can works ?

1. Yeah, expired domain should help when they have legit backlinks and stats.
2.Two keywords that will reveal most of other competitor sites are: best -product name- and -product name- reviews. So you can check there how many real competitors and amazon affiliate sites you have that will compete with you.
3.Check amazon best sellers list. There are tons of products so search and analyze the keyword traffic and competition.