This answer is for general information only and is not legal advice.
Child support and Visitation are like two pillars that each stand alone: Each is independent of the other. In the ordinary circumstance (e.g. where there is no abuse, etc), each parent must support their child, and each parent is entitled to visitation, period. Unfortunately, the only way to enforce visitation is (generally speaking) through a court order and then enforcement of that order. That means (generally) that you have to incur legal and other fees to get visitation. Unfortunately, sometimes what your rights are and what you can afford to do may be two different things. (ON the other hand, a court may possibly order attorney fees if it finds the recalictrant party was being unreasonable.)
It's much better when parties can work these things out between themselves. I encourage both parents to look at the web site http://www.uptoparents.org , which helps parents agree on parenting plans. Another brochure, "Co-parenting after divorce" can be found at the site: http://extension.unh.edu/resources/representation/Resource000191_Rep209.pdf Both of these are excellent resources which may help both you and your ex spouse see that putting the child in the middle of the parental squabble is really hurting the person you should be caring about most -- the child. Sometimes, when parents can start thinking about how to work together to achieve their dreams for their child, instead of fighting each other over this or that, they can become focused on achieving those dreams instead. The Up To Parents site in particular may help your wife imagine the possibilities and benefits for her child of having her child's father involved in caring for and nurturing his child.
Most likely, there is some reason she is withholding visitation. Most likely there is a lot of anger and distrust in your relationship. You might try writing a nice letter expressing your wish for visitation and send a copy of the brochure, above. In your letter, do not blame or express anger, merely state your need and what it would mean to you to have a relationship with your child. If you express anger, you risk just perpetuating the old cycle of arguing. The old ways of relating are not working. So figure out what you are doing that is invoking ire, and stop. You know the saying, "You catch more flies with honey than with vinegar." If she consents, you will have won your "case" without resort to courts. A "Plan B" might be to contact the Upstate Mediation Center http://www.upstatemediation.com/ and ask if they would contact her to propose mediation. Even if she wouldn't speak to you, she might be receptive to communication if it comes through a neutral party.
If mediation doesn't work, you will have to go the legal route. Good luck.