"And we cast lots- who of us should go in unto the house of Laban. And it came to pass that the lot fell upon Laman; and Laman went in unto the house of Laban, and he talked with him as he sat in his house."
This is apparently a pretty common way of choosing a person fro a specific assignment. The lots fell on Laman and he had the responsibility to go to Laban's house and ask for the plates. So, Laman went to Laban's house and tried to ease the question by talking to Laban before asking for the plates. This is pretty smart, talking to one and getting to know them is the best way of asking for something that seems not to be easy to obtain any other way.
Throw lot often use long ago. Laman himself choose go house Laban. Need obtain plate, book from Laban. Laman himself go house and chat. get know Laban before need ask for book. Smart, talk person before ask need thing maybe hard receive.