Hi Kamilah, we do have Archicad and Sketchup files that are labelled as such. The 3D Max files would be harder to find as they would be classified as 'Other'.
The two places to find files on Modlar are the Community BIM/CAD Sharing: www.modlar.com/bim-cad-sharing and the Products section: www.modlar.com/products . The products search function has a very handy formats filter, so if you do a search there (or even a blank search to see everything) and tick either the 'Archicad' or 'Sketchup' option (on the left hand side), you will only see products that have those files uploaded.
Let me know if there is anything else I can help you with!