First, I don't see any impoliteness in his messages Some people use to talk like that. You will not be able to judge a person with messages.As the title stated, i am looking for high pr backlink sites. You can do by forum posting, blog commenting etc.
what all will you do, to get high page rank backlinks. I dont need spam posts.
Secondly, you are looking for some opportunities to earn some good money. So even the client is impolite, it is his problem and not yours. Just do the job and get your payments. There are millions of dollars waiting for intelligent guys.
Thirdly, though I'm a bit late to reply this, let's talk about the subject. So, you can't face such in future without any problem.
Nipuna has clearly mentioned what will happen to you if you try to post an unrelated link (considered as trying to spam) on a forum or blog. In the case of your own place (EC), I had to ban several users for posting completely nonsense replies to technical questions. I simply ban those users so they won't even allowed to login to site again ever with that email address.
So what is the best way to build backlinks?
1. Ask the buyer to write something latest happening in his site and give it to you. So you can submit to Press Releases. Search Google ad find free site that you can submit press releases. There are many high page ranking press release sites.
2. As Nipuna stated, the second would be directories. Search high page rank directories and submit the link.
See High Pagerank Web Directories List
3. If the client can write a good technical article, you can submit to some forums and blogs with a link as see more at LINK.
For more tips, see Methods to increase traffic to your web site
Also, to submit to 500 high page rank sites manually, it will take at least a week. There are automated ways but those are not effective. So you will have to be ready for that. In a world where minimum wage per hour is $11, you will have to think whether you can do it for $30 by spending a week or so
So tell the client that the automated submission won't work properly. So to do it manually and correctly to high page rank directories, etc... you will need a better payment. I'm sure he will agree if you do a genuine job.
See link http://www.seolinkbuildingservice.com/b ... erank.html. They charge more than $115 to submit to 500 directories manually.
See link http://www.submitedge.com/. They only charge $50 to submit to 600 directories. I'm sure this uses the automated way which is considered unsuccessful.
So if he needs something for said price, he is looking for the automated submission method which is unsuccessful.