Ok on a lot of threads i keep seeing people complain on blacklist difficulty while it is extremely easy.
just make a macro easy peasy and here it is
/blist add <r>
This will add your last tell to the blacklist it wont help for the general Spam but to be honest i have not seen a lot of Spam in general for the last few days (or maybe it is because i blocked a lot of those already)
So make a macro put the icon on your hot bar get a tell press the icon and go on with your business