If you are talking about the Sandy Bridge (2nd generation) Core i3 CPU, then yes it does have an integrated graphics core. Depending on which CPU model you buy it will come with the Intel HD 2000 or Intel HD 3000 graphics core.
All mobile (laptop) Sandy Bridge Core i3 CPUs will have the Intel HD 3000 graphics core.
If you are going to buy a desktop Core i3, then only the models ending with the number 5 will have the faster Intel HD 3000 graphics core. This includes:
The Intel HD 3000 graphics core is slightly faster than the desktop Radeon HD 5450 graphics card.