I will assume you have tried the SL classifieds. I am happy to see you have used the forums.
There is some land rental specialist in second life who can assist you. One I know of is Virtual World Estate, and their website is at http://virtualworldestate.com.
SL is not as popular in modern times as it once was, and even though there are still thousands of people using this virtual world every day, finding current up to date information all over the internet can be tricky so looking inworld or on the SL website is the easiest way to find what you are seeking.