I noticed that OOTPmods is gone, but I was curious if the server was still up for Add-Ons Central. So, I used waybackmachine and found a screenshot of the webpage. Then, I followed the directions and it turns out you can still access the server in Add-ons Central. Go to "Add-Server" and put in:
http://ootpmods.com/mods/ootpmods18.xml
All mods should be compatible. Edit: I should warn, there isn't a huge up to date selection.