Where was it?

Scholars do not agree. Every proposal recorded by the source is shown with its support score, so you can see the weight of opinion rather than a single answer.

Proposed site: Tell edh Dhahab el Gharbi · telOpen in OpenStreetMap

Tell edh Dhahab el Gharbi654

32.1857, 35.6867tel

Tell Hejaj63

32.1495, 35.6924settlement

Tell edh Dhahab esh Sherqiyeh29

32.1870, 35.6921tel

Tell er Reheil0

32.1296, 36.0539tel

Sleikhat-12

32.3231, 35.5933tel

Khirbet Mehna-58

32.3639, 35.7488settlement

Names

Mahanaim — מַחֲנַיִם mahanayim “double camp” (H4266) · Παρεμβολαί Parembolaí “camp” (G4213) — Genesis 32:2

References

and 1 further references.

Topical references

The place where Jacob had the vision of angels — Genesis 32:2
The town of, allotted to Gad — Joshua 13:26; Joshua 13:30
One of the Levitical cities — Joshua 21:38
Ish-bosheth establishes himself at, when made king over Israel — 2 Samuel 2:8
David lodges at, at the time of Absalom's rebellion — 2 Samuel 17:27; 1 Kings 2:8

Outline from Nave's Topical Bible (1897); the sub-headings are Nave's own.