Take a few minutes and do some reading
hereThere are sub forums where you will find a lot of advice. There are lots of brands and models from pretty basic to loads of bells and whistles ( my machine talks :C) . Some of the sponsors are known to very helpful as well. I have a Garrett machine and find their customer service to be top notch when I need help. If you google 'metal detectors' you'll find the sites of different manufacturers and some of them have good info. And don't forget youtube to see and hear machines in action!
You don't want to look like a dweeb? Really? That kinda comes with the territory for MDers. Real life detecting isn't like those fancy TV shows, where the guys are oh so cool ;) There's no way to look chic or debonair as the case may be while you're wearing cargo shorts, sensible shoes, a sun hat, headphones, and fanny pack or pouch, and swinging a big metal stick in front of you LOL.