There was interesting discussion on eharmony's advice website regarding whether or not to discuss faith on the first date. This is an issue with which I sometimes grapple.
For a long time (ever since I became "interested" in boys), I said I only wanted to pursue romantic relationships with Catholic men. However, I never could get into a relationship with any Catholic guy (or actually any guy). Also, when I decided to actively choose childfreedom (rather than "waiting to see"), I realized I had to expand my dating horizons beyond Catholic boys. All the good Catholic boys want to have a litter of Catholic children. For me, children is the dealbreaker, and I don't yet know if religion has to be.
In terms of whether or not to bring up faith on the first date or early in the relationship, I don't bring it up unless my date brings it up. Because my dates have all been with guys I met online, though, they know I'm Catholic before we meet in person (it's in my profile). I also mention in my profile that faith is important to me, but I'm not perfect and open to dating people of different faiths. On a Christian site, I go on about all the Christian groups with whom I'm affiliated.
Now, it seems logical to bring up religion right away if that's really important to you. However, even though I don't consider myself an evangelical Bible-thumping Christian, if I bring up too much about my faith too fast, I know I'll come off as an overly righteous "Jesus freak." It's not that I'm ashamed of being Christian or am trying to hide it. I believe the best way to evangelize is to LIVE like a Christian. But I guess if you're the type that's, to put it nicely, very open and assertive about your Christianity, then you have to put it on the table early with a, "This is who I am, take it or leave it" attitude. If you need someone with as assertive as faith as you, though, you probably should just stick with Christian singles sites.
St. Francis said "Preach the Gospel at all times. When necessary, use words." One of the songs we sometimes sing at Mass has a line that says, "And they'll know we are Christians by our love." I prefer to "show" that I'm Christian rather than "tell" that I'm Christian.