Taking LSAT in Oct, what do you think I need to make on it...
As high as you can possibly get. Don't shoot for admission, shoot for scholarship money and hopefully lots of it.
...do you think the admissions will take into consideration grad school GPA
No, they won't. Undergraduate GPA and LSAT score are pretty much all that matter unless you've done something spectacular, like cured cancer.
...what is an addedem(maybe spelled it worng)
Addendum. And you should write one to explain the very large disparity between your undergraduate GPA and your graduate GPA. Don't use "apathy" as an excuse; try an approach more like, "I was immature and lacked direction, but matured in the second half of undergrad and did much better--see my graduate GPA? Awesome, huh?!?!"
And if I get a 165 on the LSAT what top 50 school would be splitter friendly
Do a Google search for "law school admissions calculator" and go through those to get an idea of where you'll land with different numbers. But again, don't shoot for a number, shoot for the absolute best you can possibly do.