Anyplace single girls are is a good place. This can include bars, the beach, the grocery store, the park, etc. You just have to have the nerve to start up a conversation with a girl you find interesting and not give up if it doesn't work at first.
One thing to keep in mind is that you probably don't want to meet someone out drinking or at a nightclub. Look somewhere that has something you'd like your eventual partner to be interested in, like the library, or a coffee shop.
The best place to meet girls is at church functions. Churches have picnics and volunteer events. Everyone at these events is friendly and interested in meeting other people. You will meet many girls there.