Here is what I did to train my dog's recall. She's a Jack Russell so she has pretty much the same temperament as yours.

I used to walk in places where I knew there were not too many distractions.. and definitely no dangers like cars and so on. She was off leash and running ahead of me.. When she didn't look I would hide somewhere where she could not see me but I could see her. When she noticed I was gone she started looking for me and then I would call for her and when she came to me there was of course lots of praise and a treat.
Doing this frequently has taught her to pay more attention to me when she walks off leash because she doesn't want to lose me and now she has a very reliable "come here".

You can do this training on a long leash, if you don't feel certain that she will come look for you. Just make sure it's a very long leash so she feels like she is free.

Also when you're walking your dog. Call her to you frequently. Hold the collar and praise her and then let her run again (perhaps with a command to it.. like "free"). It's very important that she doesn't start to think that "come here" ALWAYS means "fun time over".

-Varga