What are the connotations of "Pesorah"?
Rashi #1: It describes Bil'am to a banker, 1 inasmuch as just as everyone brought him their coins (to check or to exchange), so too, did everyone bring Bil'am their letters (to decipher).
Rashi #2 and Targum Onkelos: It is simply the name of the place where Bil'am lived. 2
A bank in former times, consisted mainly of a table ('Pesorah' is also the Arama'ic for 'a table'), on which all transactions were performed and behind which the banker sat.
Targum Onkelos: Aram (Naharayim) on the River P'ras.
Targum Yonasan: Who was so wicked that he actually went to curse the descendants of his own grandchildren!
See Ba'al ha'Turim.
And what are the connotations of "Eretz b'nei Amo"?
Rashi, Ramban #1 (citing the Midrash Rabah) and Rashbam: It means that Bil'am hailed from the same town as Balak. 1
Ramban #2: It means from the land where Bil'am was born and where his Yichus lay. 2
Targum Yonasan: It means that people from all over came and bowed down to him.
Why did Hakadosh-Baruch-Hu grant prophecy to a wicked Nochri?
Rashi: So that the Nochrim would not be able to claim that, had Hashem given them prophets, they would have followed the right path. So He gave them a prophet, and what did he do? He broke down the barrier
What are the implications of "Likro Lo"?
Rashi: It implies that Balak offered Bil'am a lot of money to come and curse Yisrael. 1
And why did Balak add "Hinei Chisah es Ein ha'Aretz"?
Rashi: He meant metaphorically that Yisrael had defeated Sichon, who guarded them, and that they therefore constituted a threat to Mo'av.