@raj kumar - I don't have the answer as to where to buy them, but I have seen it mentioned. I can't imagine it would do you any good since Google will most likely know that they are fake.
The whole social thing for me just seems to stink. I have the buttons, but people don't seem to be sharing. As to buying them, I have to ask myself, is that really bringing value, trying to trick Google? I think most people would say no and eventually things like that would probably backfire. And just clicking each others' sites as a favor would also seem smelly.
Certainly trying to educate your readership on how them sharing can be beneficial to your site would seem logical. And I do click the various social buttons on other sites when I find the content worth sharing.
So I guess to answer your original question, education would be the best way to get more clicks. :O)
I remember when Adwords first started, there were tons of theories about how doing Adwords for your site worked like a back door for getting better organic listings as well. It seemed to work for my clients, though I could never be certain because we were doing many other things at the same time. If it were true, I could totally see how they were following this strategy again with G+...supporting those that supported them so to speak...
I'm sure that most would agree, and it's been written in these forums many times over that natural is best. Just as links will grow naturally (barring anything viral), so too will Plus clicks. Whether slowly or quickly, if there is something to relate the click back to such as a good article, then it will look natural. If the same person were to click multiple items on the same site within a very short span, it would look very suspicious, one suspects.
Until some of the fog lifts on how much impact Google + has on SEO I believe it will have more impact on your personal search preferences. You have to be logged in to your Google account to use +1. While you're logged in any searches you make (related to stuff you like or plus'd 1) could be run through the +1 filter. That said, I'd imagine Google reserves the right to use +1 in some way to weigh in on organic results.
To get one to click on +1 I'd advise the basics. Display prominently and ask, which you've basically pointed out as a solution to your own post. Clicking your own +1s will reveal them to your "circle" of Google friendlies. I don't think there's harm in that. Forming some coalition with a group to favor each others pages, articles, posts, etc. shouldn't cause a penalty of sorts, but I'm sure Google reserves the right to penalize at will.
It won't hurt but I don't think it has a huge affect on positional ranking. It is too open for abuse. But if you've got 5 bucks to waste, go over to Fiverr, ante up a nickel and get 400 likes or more.
There's one thing we know for sure and that's that when we create a Google+ page for our business/website if we add a website to our about page during stup that Google states explicitly that adding your website in that section "helps your site be found easier".
Now seeing Google conglomerating their entire network more and more we can safely assume that our links will eventually be found in all types of diverse places across their network. And this falls in line with the idea of not worrying about the search results anymore. Pagerank or not there will be times when a highly plused website will rank above a highly (page-ranked) website.
I've found that if I just click the Google Plus button on a site or post, I can simply Plus it. However, I can massively share something I really like by sharing it with my circles. So, I believe there is a distinction here. And, when I do one of these larger "shares" there is much more interest from the search engines.
I think +1 buttons are a good thing to combine with the SERP's for better results when you are logged in. Based upon your interests and browsing habits these results should appear more relevant. I think +1's should come from many I.P addresses to make it look natural, If you +1 a bunch of sites and pages from the same I.P address Google probably knows this and devalues the +1 rankings in the SERP'S. If you buy them, get them from a company that uses multiple I.P addresses. If you are going to exchange +1's then I would do it in correlation because like link correlation Google uses +1 metrics in the webmaster tools to tell you what pages have been +1 and Shows you the impact on search by showing you the +1 impressions.