###Simple Fix
You can get the Steve Skin on Minecraft.net
- Log in, go to Profile
- Download the reference skin
- Upload the reference skin
In this case you will have a Steve skin.
###Problems
Uploading the reference skin still counts as there being a skin, because, well, it is there. The problem here is that skins uploaded to the skin server take precedence over skins included in Resource Packs (e.g. the default skin in Sphax PureBDCraft).
Unfortunately there's no way to remove the skin from the skin-server completely.