Custom

How do you make custom items in the Sims 3?
Body-shop related items? (hair, clothes, etc) I remember how to open it up and all in the sims 2, but how do you do that in Sims 3? And I have various programs all over my computer, but do you have any suggestions of which I should for creating custom items?
As far as i know The Body Shop does not come with the Sims3, therefore it is a more complicated way to make clothes, they have alot of information on this site about creating Sims3 custom stuff
Hope this helped
http://modthesims.info/
Custom – “Beat Me” ARTISTdirect Records