Looking to dabble with GAE and python, and I'd like to know what are some of the best tools for this - thanks!
I would spend the time and learn something like emacs. The learning curve is a bit higher, but once you get used to it, you can develop from any terminal. It has fantastic support for python and many other libraries.
You have to remember that Python is a dynamically typed language so the traditional IDE is not really the answer since those are mostly designed for statically typed languages. Basically you want something that has syntax highlighting, compilation and maybe some shortcuts and macros to make life easier for you... emacs has all of this :)
I would Google "Emacs Python" to get started.
If you really don't want to use emacs, I would look at PyDev. It's an extension to the eclipse IDE that let's you write python code. Some of my friends that do Django work have had good luck with that one.
Hope this helps.
Good luck with GAE.
VIM(there's enough plug-ins to make it IDE -like)
Komodo IDE($$)
Eclipse w/Pydev
Net Beans with Python support
WingIDE($$)
SPE(Stani's Python Editor)
I've been using gedit and am pretty happy with it, there is a couple of good plugins that make life easier (e.g. Class Browser). I tried eclipse but its just not the same experience you get with Java.
For my recent GAE project I tried both eclipse with pydev and intellij with its python plugin. I use intellij for my "real" work and so I found it to be the most natural and easy to use, personally. It is not open source, but if you already have a license it is no extra cost.
I found the eclipse plugin to be very good as well. You don't get as much intellisense as you would with java, but I was very impressed with what you do get from a dynamically typed language.
Similar question with a lot more answers:
http://stackoverflow.com/questions/81584/what-ide-to-use-for-python
If your on the Mac I would highly recommend TextMate. The IDE is great for coding on projects like Python, PHP, Ruby on Rails, HTML, etc.
The price is $52 US and there is a 30 trial version that you can get to try it out for yourself. Highly recommended my most Mac Developers.
Also if you watched the demo's at Google Campfire you'll notice they are using TextMate!