http://www.mahoodsculpture.com/ceramic-sculpture-techniques/
Does anyone knows a web site where I can learn more about making sculptures; specially ceramics?
I had done a sculpture in a class of ceramics, but I want to know more about it (By example, the techniques and materials available.)
Any of the techniques that you used in your ceramics class can be used to make ceramic sculpture, especially hand-building (though you can certainly throw and then alter forms). Things you can try: pinching clay into the forms you want to create; coil built forms; building by addition (adding clay to more clay); building by subtraction–carving to achieve the form you want (scraping away, etc). You can even roll out a slab, and then build or twist pieces into sculptural forms.
Honestly, I wouldn’t recommend any website, even if I knew of one. This is one of those “hands on” things. You really should consider taking another class, one specifically in sculptural ceramics–and learning techniques right there in the studio.
While you’re at it, you might want to consider taking just “general” sclupture classes. Learn about working with a variety of mediums. While my Bachelor’s degree is in sculptural ceramics, I’ve done art welding, wood sclupture, found object sculpture, mixed media sclupture, etc. The great thing about learning and mastering different mediums is that, once you’re gotten through it all, you can combine mediums–truly expanding your horizons and opening your mind to more possibilities.
Randal (above) had a very good idea about mould making. This is something that I learned in general scupture (I think it was Sculpture II in college), and is something that I do regularly. I’m not sure that you’ll learn about making moulds in ceramics, though it’s certainly worth checking out.
Good luck to you! 
Radical “dipstick” paperclay sculpture technique (199402)