Is it allowed to create a website with my own models for people to download?
If you are giving them away for free you could do that. It might be easier to use the 3D Warehouse and provide links to them on your website.
Thanks Dave! They will be for free, but there will be ADS on the sidebar, is that ok?
I don’t know. Since you are using SketchUp Free and some might construe your use as commercial since you would be making money from the ads, it might be against the agreement you made. I think if I were you I would consult legal counsel to make sure. Might actually be cheaper to get a license for SketchUp Shop which would remove any question.