It could be eczema, dermatitis, or anything along those lines. The only way to know for sure is to see a doctor. Peeling skin can sometimes mean a fungal infection, but since it hasn't spread or gotten worse for so many years, I'd have to think that's not it.
Don't try any creams at home - get it diagnosed first. A lot of creams for eczema are not meant for the penis, especially for the sensitive head of the penis, and you could make things a lot worse.
If lack of insurance or cost is a factor (if you live in the US), call your local health department and ask what resources they have for someone with your financial situation.
Let us know what happens.