You'll end up getting hooked. My website is an ongoing project for wet winter days and I think it will take me years to complete.
Start with a small idea though and let it grow from there, they seem to evolve as time goes by.
I did a course in website design with the Open University a couple of years back and the one thing that I learnt which is really good advice is to draw on paper exactly what you want each page to look like before you even start designing it. I have found that to be very good advice.
Kerry