Shameless Self-Promotion:
My company makes a product called 3D Language, a virtual environment where you can practice speaking Spanish with the characters via voice-recognition. It isn't a full course to go from nothing to fluency (yet), but it works as a supplement to other products, so you can actually practice having conversations with people at your own pace.
Try it out:
Learn Spanish With 3D Language
The demo is free and the add-on lessons are pretty cheap.
Jeff