What is the best way to let the employers see your StackOverflow or LinkedIn profiles with ease ?
Don't use a recruiter, or find one that will allow it. I'm not trying to be snarky here; it just seems like the only solution.
I don't have much experience with recruiters. However, my understanding is that at least some of them have close working relationships with the companies for whom they are doing the recruiting, and wouldn't be afraid of companies making an end run around them. So I don't think it would be an issue for everybody. If this is important to you, then make that clear to the recruiter, and don't work with them if they insist it must be removed.
Is it wise to print SO and LinkedIn info on Business card and share it with interview during the interview ?
I don't think this is so helpful. Before you get to interview is the time when this information would be most valuable. A resume is basically a tool to get you to the interview. Once you are there, the impression you make face to face is most important.