Linking Your Own Sites Together

So today I was on a website buying spree to get everything ready before school starts for me tomorrow but when I bought these domains I got a free .info site with the same name and I don't really know what to do with these. (No, I'm not going to hand out freebies )

So, I'm thinking that maybe I can just make a quick 4-5 page site and link the site back to my other .org site. Thing that should be noted are that these sites have the same name except for the TLD and are under hosting using the same IP address. It seems like it could be a good idea but I don't actually have experience doing this and don't want to risk my sites/adsense account.

ALSO: I don't want to make a flurry of threads all of a sudden so I guess I'll ask it here. Are sites like Amazon, Radioshack, Walmart, and Nextag possible to outrank. I'm seeing all of these sites on first page but I have the general domain name. What I mean is:

Let's say the domain name I can get is: "awesomedog.com"

Let's also say the keywords are:

• awesome dog tags
• awesome dog leashes
• awesome dog clothing
• awesome dog costumes

These sites are big authority sites and the pages ranking have high PR but a low number of backlinks (<10 backlinks) so I think they might be beatable. But the truth is I have never even ranked #1 on Google for any of my keywords, closest being #2, so I would still say I'm in the learning process of SEO.