I plan to make 3 to 5 web 2.0 websites as backlinks directly pointing to my website. Do I need to make these websites on 5 different computers, and hence, 5 different IP address, or is it okay to build them on one computer (my own), which means all website is built in a single IP address? They say that website must be built on a unique IP address for it to be a valuable back link.
If you're building those 3/5 web2.0 sites on different networks like blogger, wordpress or tumblr (1/2 site on each network) then yes it is ok to build all those without proxy or multiple computers.
probably u misunderstood something "They say that website must be built on a unique IP address for it to be a valuable back link." it is about building sites on your own domain, not freehosted blogs
So, does this mean that blogs on free flatforms such as blogger.com, WP, blogsome, and, weebly have no value whatsoever if used for backlinking purposes?
Your getting confused on diversifying IP addresses. For example, your using one computer (like me). Then you post articles on 5 web 2.0s properties such as squidoo, blogspot, weebly, etc... You'll eventually end up having links on domains with different IP addresses, the IP address of the hosting server if I'm not mistaken. But, there are people who makes 50-100 postings on web 2.0s for getting links for their different sites. So they use proxies so not to get banned on those web2.0s properties for having different accounts. If you want to use proxies, then I recommend http://www.hidemyass.com/ . . . But at this moment I think you don't need to use proxies. Ohh, having links on web2.0s properties are still working good. Also do some guest posts if possible.
when you build a blog on a free hosted site, it doesn't show your IP on the blog publicly so it doesn't matter you build them from one PC or 5 PC. they have great value and should be included on every single SEO campaign. web 2.0 pages provided relevant contextual backlinks. how can they have no value?
Don't understand. Many say that if you build this web 2.0 websites - for example, one blogger.com, one weebly site, one wordpress site - on a single computer; all these sites will have the same ip address of that computer, thus rendering backlinks coming from them to be of low value. Others suggest that if you want to build web 2.0 websites as backlinks, build each and everyone of them on a unique computer. ONe computer with unique ip address to a single web 2.0 website.
It's up to you on to whom you will listen. As for the value of using web2.0 properties as backlinks, you'll eventually end up on a PR0 but if you will send backlinks to them (TIER2), then some of them might rank or they're PR will increase, either way you'll get a good juice of backlinks pointing to your site. But do not rely on just one backlink method. And don't complicate SEO too much and maybe this is giving you information overload that could stop you from doing things. Start with web2.0s and wait if its pushing your site in rankings. Then do relevant blog comments (never spam), do a press release, do some guest posts, video submissions. Just do it and see your site go to the top. I suggest you personally do it and just hire good writers to ease your working load. Because if you outsource it cheap, then you'll get what you pay for. Doing it yourself, you'll learn more and grow up because of experience. P.S. you could use one computer. If you still have a doubt, ask them to explain it here on why your backlinks will end up on the same ip address if you only use one computer.
I do hope there is also no problem if I update and maintain my main website, and create the websites 2.0 which I will link to it on the same computer.