“It's been my experience that Wicca & Paganism can at times place a heavy emphasis on Goddess & feminine energies. In a path that honors women's mysteries, is there such a thing as men's mysteries? and what could distinguish men's spirituality from spirituality in and of itself?”
It is true that there is an apparent emphasis on Goddess energies and Women's Mysteries, although the two are not the same thing.
The apparent emphasis on Goddess is a reaction to centuries of patriarchal religions where the Goddess is never even acknowledged. Some people, especially those new to the craft, rebound heavily to the side of the Goddess, once they have discovered Her. In my opinion, this is just as imbalanced as those who only acknowledge God, but most Wiccans not following a Dianic tradition eventually achieve a bit of balance between God and Goddess. (We hope!)
Sometimes, it's just so unusual to hear people use the word "Goddess" at all that it stands out in a conversation. This doesn't necessarily mean that more emphasis is placed on Her, but the perception is there.
As for Mysteries: Absolutely, there are Men's Mysteries! Being a woman, I wouldn't presume to instruct you, but I am certainly aware of their existence. At just about every pagan gathering I've been to, there's been some sort of "Men's Mysteries" ritual to complement the "Women's Mysteries" ritual. I've never attended (naturally) but from what I've seen, it involves a lot of drumming, howling, sweating, and energy work. (It always sounds like such fun!)
So feel free to connect to Goddess AND God, and celebrate your masculinity. It definitely has an equal place within the craft.
~Flame RavenHawk