Do Follow Social Bookmarking Sites... Really?

Hi, my first question would be what are trying to achieve? this may guide to why you are not getting the results you want.
Helping people to succeed
Robert G Williams

they do exist actually.I suggest that you use social bookmarking sites that has a PR or 1 or 2. they do help too. beware of some PR 0 site because they dont help your site and might drag your website down. focus on other link building strategy like forum posting, blog commenting, guess posting. they help alot.

If you check the home page of the social bookmarking sites then you will find that almost all the site links are dofollow.Upcoming pages are nofollow.
If you can get some votes or ups on your links then they will be sent to the front page and will get dofollow link

Yes, there are lots of dofollow bookmarking site like reedit

Yes Sir, They do exist.
Just do little bit research, You will get it.
Usually social bookmarking sites offer dofollow links for published ones and nofollow for upcoming ones, And submitted links move from upcoming to published depending upon the number of votes.

I also have a list of such sites (not so big but useful)
here is the list: High PR Top 10 Dofollow Social Bookmarking sites

They can only help you gain some new visitors to your website... almost nothing more. They can't help you (about 95% of them!) get a better ranking in google.

Dofollow is the opposite to nofollow and they have different meaning in SEO. As we know, if one word marked with dofollow, that is to say the links of keywords can be traced by search engine spider. However, nofollow means it does not transmit the link juice for websites. Nowadays, more and more websites choose to add nofollow to prevent other websites build backlinks on their websites. Thus when webmasters build external links, they prefer to the target websites with dofollow tags and only the dofollow tags can be accepted by search engine. And then transmit link juice in order to make more traffic and benefits for themselves.

Due to the popular used of nofollow, it becomes more different to find one website without nofollow. More and more people realize the importance of nofollow to their own websites. Thus it is becoming more difficult to find a dofollow social bookmarking site for a new SEOer. So there are some tools appeared as people`s require. Some SEO tools, especially submission tools, can provide this functions for users. Then people can submit information and build more backlinks on various social bookmarking sites with do follow. Also the backlinks is useful to web optimization and if the social bookmarking sites have a high PR value, it will do good to increase the link juice of ones` own websites in some degree.

By using the submission tools, people can make clear of details and almost all of the sites provided are dofollow. Therefore, the tasks you did with tools is also meaningful and helpful to bring more traffic.