Where to go now?

Hi.

I just finished all the projects with the sparkfun inventors kit.
I am now looking into getting started with a little more advanced stuff, but where do i go?

I have been thinking about getting a motor shield, but don't know which one to get.
I have found this one, which looks interesting Adafruit Motor/Stepper/Servo Shield for Arduino kit [v1.2] : ID 81 : $19.50 : Adafruit Industries, Unique & fun DIY electronics and kits but i am not sure how to go about it.

Anyone have anysuggestions to which i should get?
Also, i am thinking about getting a battery holder for my arduino UNO, so it can power itself, but i am also seeing that this shield has the ability to use seperate power supply. Can anyone tell me i f should keep an eye out for any specific battery holder, and which kind of voltage i should use to power them?

Thanks.

It doesn't much matter which motor control shield you get if you are just experimenting. Get one and play with the examples and tutorials you can find that use it.