What do you think is a good IDE for learning SmallTalk? I'll only be using it as a hobby, so it has to be free.
Smalltalk/X came up on Reddit the other day. It looked pretty good.
I think Squeak is the way to go. It has an entire smalltalk environment and is constantly updated. Its what I used for learning and is actually even a cool app in itself.
You can also use Cincom Smalltalk or Dolphin Smalltalk. They both have community editions.
Squeak is free. Cincom has a non-commercial version of VisualWorks. GemStone/S is free for small installations. GNU Smalltalk is "free" in the GPL sense.
Definitively go for Squeak. It's a closed system in terms of the environment, or what you call the IDE, but it's fun to do webapps with - look for Seaside. However I always recommend everyone involved in development to take a look at it, just to understand how development in an image is working - and to experience a live system.
The main problem with Squeak, or maybe Smalltalk in general, is that once you get used to it, it's very hard to go back to the conventional way of programming.
Besides, I heard that you might become a better programmer if you work for some time in Smalltalk. I don't know if that's true, but I certainly like to think so.
You should also consider Pharo. Pharo is a fork of Squeak. Their goals are:
a clean and lean open-source Smalltalk platform, derived from Squeak
the obvious choice for professional Smalltalk development
an emerging platform to help people invent the future
Whether it is Squeak or Pharo, there is a large, active and supportive community.
If you start with Cincom Smalltalk, there's a ton of learning material available:
-- tutorials -- daily screencasts -- videos -- weekly podcast
You can find the screencasts, videos, and podcasts on iTunes - just search for "Smalltalk" in the podcast section.
You won't need a separate IDE because smalltalks usually come with their own IDE, so choosing your smalltalk flavour pretty much determines the IDE for you. Don't let this fact scare you off from taking on smalltalk though!
WRT your original question, I had two wonderful years developing in Dolphin Smalltalk & highly recommend it.
Dolphin Smalltalk is only as free as a beer is though. If you need an opensource smalltalk go with Squeak.
In my opinion Dolphin is the more polished/comfortable/user-friendly one.
If you are used to Eclipse or Visual Studio, and are running on Windows - then Dolphin is something that will feel very familiar to you. It looks very nice (no emulated widgets, as its not trying to be cross platform), and it has nice touches like code completion and a graphical window designer (rather like IB on the mac). It also has great refactoring tools and can easily create small .exe file (e.g. 500k including the vm). There is a little screencast of doing TDD in Dolphin
Of course, these things are available in other dialects - in particular Squeak Pharo looks very promising particularly if you are after an open source product.