You may get custom content from the official Sims 3 Exchange. However, if you would like more variety of content, there are always third-party sites such as The Sims Resource and SimsVIP. You may find the links to these sites below.
You can find custom content on various third-party websites, or by downloading pre-made Sims with custom content from the Sims 3 Exchange.
Happy Simming! <3 FSC
custom content is legal for the sims 3 and any other game,unless it breaks copyright laws
Here are some custom content sites.The Sims 2 ExchangeThe Sims 3 ExchangeModTheSimsThe Sims ResourceGarden of ShadowsSimbologyMore Awesome Than YouInsimenatorLianaSims2AnnaMariaSims2DecorgalThe Sim SupplyxSIMS.de (mature content)There are plenty more sites than this. If you want more just google "sims 3 custom content".
You can have one, but custom content is required.
By having TSR workshop for custom content or if you want to get custom content go to Modthesims3.com or TheSimsresource.com
If you know how to make custom content then you can. Mod the Sims has a "how to" tutorial on custom content.
I highly doubt this is possible. You can make a 'look-a-like' of something but you cant bring something from the sims 2 into the sims 3.
No, although you can download custom content braces online (see modthesims2.com).
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Custom content.
You can download custom content a lot of places online, such as Mod the Sims. Just create a log-in, go to the "downloads" tab, pick The Sims 2, and start hunting.