Yes, the initial onslaught of interest when you first sign up is normal. It'll slow down.
I've gotten good at ignoring the crazy sounding profiles. A lot of times I will say a simple 'Thanks but I'm looking for someone local' which ends the emails.
In the last couple of weeks, I've been in contact with a few men I've met online. It's refreshing when the respectable ones do NOT ask for "more pics". After talking about two weeks, I went out on a first date last night with a very nice man (and HOT!!). Hopefully things go well.
You just have to be patient and weed through them!