"A rose by an other name would still smell the same!"

Surnames:

Surname Meaning/Origin
A basic understanding of Polish naming conventions. Includes examples and a table with translation of some prefixes and suffixes used in Polish names.

Family Surname Suffixes
Adding a suffix to family surname was a fairly common practice. This article by Joe Armata explains how a name may have been different depending on considerations for gender, family position, or where a family was from.

Polish Name Conflicts
Understanding why looking under "W" for a Polish surname like "Valewski" might lead to success.

Surname Meanings Board
Meaning or origin of surnames sent in by viewers. If your surname isn't listed, then help us put it there for others to know as well.

Given Names:

Given Name Cross-Reference (pdf)
Table converting English given names to their essential equivalent in Polish, Czech, French, German, Hungarian, Italian, Slavakian, Russian and Yiddish. (this file requires Adobe Acrobat Reader to open)

Names: A Logic to Understanding
So your grandfather was known as known as "Stanley" therefore his Polish name must have been "Stanislaw". Don't be too sure! This article by Stefen Wisniowski gives a logic for understanding how "Americanized" names may be something other than what is obvious.