I need some advice plz - backlinks!!

Hey Guys

Im new into SEO and IM and was looking for the following answers to my questions, please dont get me wrong i dont want answers like GOOGLE IT just want the best advice from the experienced SEO guys or anyone who knows how to help me please.

1) I get confused when I hear about Social Bookmarking, as some people say you need to do that for each article on your blog to get backlinks and some people say its only used for indexing a site, what really is it used for?

2) Directory submissions what really is this for??

3) Web directory what is this for too??

I mean I am looking at ranking for low comp keywords "keyword" - under 50k, and top 5 isint that bad maybe with atmost 300 backlinks.

now what I was thinking was the best way to get these backlinks, I was thinking of profile links, edu links, but can anyone tell me what would be the best way to do this.

I have keyword domains, so i guess that is an advantage but just really need some advice which services should i be doing as what exactly should i be concertrating on

1) Social bookmarking - WHY
2) Directory Submissions - WHY
3) Web Directory Submission - WHY
4) Article Submissions - WHY

Thanks in advance guys!!!

Im sorry if I have put this post into the incorrect section, if so please MOD can you move it to the relevant sections plz, sorry First Ever Post!!

1) its used for backlinking in most cases. It works for both indexing and building links.
2) same answer - backlink building
3) ??

Just build links and see what happens. Asking "what ifs" on a forum won't rank your site.

Note: just about every link building method you listed is sold as a service here.

Profile links - don't do it manually. There are a lot of different programs available.
Social bookmarking - sold on BHW for really cheap. I think his name is Ankur.
Directory - Ankur again

If you build links with each of the methods you listed then you will rank. I would make sure that you site is indexed and then build 5-15 links a day if that is a brand new domain without age.