Watch this thread to be notified when updates are released to the official texture packs.This includes both the Creative pack and the General pack.
You can find all the information you need, including download links over on the Wiki.
You may also post any suggestions or improvements you would like to see happen to the pack in this thread. Your suggestion will be looked into, though there is no guarantee I will be able to do it. If you would like to see a texture changed, please be descriptive so that I know the exact texture to change, and what you would like done with it. If you have a specific texture in mind, try and post a screenshot of it, as this will make my life much easier.