In regard to the specific request regarding background information from scripture about Abram's the mother one has to say the bible is virtually silent
The Bible does not identify Abram's mother, only his father.
Gen 11:26-27 Now Terah lived seventy years, and begot Abram, Nahor, and Haran.This is the genealogy of Terah: Terah begot Abram, Nahor, and Haran. Haran begot Lot.
In fact the only reference to her is found in Gen 20:12 we reads: "But indeed she [Sarai]is truly my sister. She is the daughter of my father, but not the daughter of my mother; and she became my wife.
However considering that Abram was called out of Ur (with his father) it is most likely that his mother was a local girl rather then one brought on a long journey from Canaan.
If the detail of Abram's mother was significant to the story I think the blanks would be filled in. I appreciate this is akin to an argument from silence but this is a hermeneutics board and one principle of biblical hermeneutics is that if the bible doesn't give us a detail that detail is not pertinent to our understanding of the story.
In regards to other Jewish sources in the Talmud (Baba Batra 91a) we read that her name was Amathlai, here is one translation of that portion of the Talmud
R. Hanan b. Raba further stated in the name of Rab: [The name of] the
mother of Abraham [was] Amathlai the daughter of Karnebo;
Kernebo could be 'lamb of nebo' and a reference to the mount Nebo, which is the place Moses stood upon to look into the promised land (Deut 34:1) which could, if the source is reliable, potentially suggest a close racial link, i.e. make her a canaanite. However that is supposition. Nor do I the know dating or reliability of this document in regards to historical details like this.
There is also one Midrashic legend about the birth of Abraham that can be found in Midrash Avraham Avinu, found in Ozar Midrashim (ed. Eisenstein, 1969, vol.1, pp., 2-3). Another, slightly different version of this story appears in Sefer Hayashar, P. Bereishit, pp.18-21. (source http://www.jewishmag.com/162mag/abraham_mother/abraham_mother.htm)