I am starting to become more interested in Messianic Judaism and so I am wanting to ask a question or two.
Is there unity among Messianic Jews, or is there different sects?
Sects? I don't know if you could call them sects. However, there are different umbrella organizations that congregations belong to.
To oversimplify, there are two basic groups. There are 'Hebrew Christians' who's roots come from the church and are seeking to explore the Jewish roots of their faith. Then there are 'Messianic Jews' who come from various Jewish backgrounds, and are seeking the meaning of Yeshua in a Jewish context. The two groups, don't interact much. I belonged to a MJ congregation for many years, and know we didn't have much interaction with the local Hebrew Christian group. I dropped by once to their Friday night services. Not a shabbat service, it was a prayer/social service. They met on Sunday to worship. The gulf... just too wide. Both groups would call this DIR home, but frankly the few (very few) people I've seen come here were all MJ and none of those were 'Hebrew Christan'.
And where can I find out more about Messianic Judaism?
I'd start with Green Gaia's Overview. Most of the articles here are mine, they may be of interest. Google of course, keeping in mind that both groups I mention call themselves MJ and therefore conflicting opinion is a given.