A detailed analysis of Japanese surnames is available here.
Kanji Clinic #40, The Japan Times, July 17, 2003
“The kanji behind the most common Japanese surnames”
Business cards (meishi) are almost as “Japanese” as sumo wrestling and kimonos. These handy bits of paper help to oil the squeaks out of potentially awkward first-time encounters in Japan, promoting smooth starts to business and social relationships.
Japanese people who are in frequent contact with foreigners often carry double-sided meishi: Side 1, for native consumption, is chock full of kanji; Side 2, meanwhile,
is printed in English and Romanized Japanese. If you want to make a special
impression on a new Japanese acquaintance, flip their meishi over to Side 1 the moment you receive it, and get excited about trying to translate their surname into English.
Pronunciations of names can be a headache, even for native speakers, but
approaching surnames through English keywords can build your self-confidence.
Incidentally, surnames are a piece of cake compared with given names, which
are more likely to include obscure kanji.
Mastering the shapes and English meanings of 25 core surname-kanji will give you a firm grip on the meanings of Japan’s 20 most common surnames, held by 19.5 million people (nearly one-sixth of the population):
木 山 田 水 井 口 本 中 上 小 高 林 松 村 橋 加 吉 辺 清 渡 伊 佐 藤 鈴 斎
If you have completed an introductory Japanese course, you probably know 12 of the 25 already: 木 (tree), 林 (grove), 山 (mountain), 田 (rice field), 水 (water), 井 (well), 口 (entrance), 本 (origin), 中 (center), 上 (above), 小 (small), and 高 (high).
By using mnemonic stories, the next eight of our kanji surname building blocks are a relative snap to remember [Most of the following memory aids come from Joseph R. De Roo’s 2001 Kanji (Bonjinsha)]:
松 (pine tree): Tall trees 木 were planted along public 公 highways so that government couriers would not stray off them at night.
村 (village): Moving through a wooded area, a traveler sees trees 木 chopped off short (寸= “just a bit”) and knows a village must be nearby.
橋 (bridge): A wooden 木 structure built so high that the first two strokes of tall 高 have been replaced by sky 天.
加 (add): Strength 力 depends on continuing to add food to the mouth 口.
吉 (good luck): A samurai 士 opens his mouth 口 wide with joy at his lucky lot in life.
辺 (boundary): Roads 
are sliced up with swords 刀 to create boundaries.
清(pure): Sometimes water 
is so pure it appears to be blue 青.
渡 (cross over): When the water level (度 = “degree”) is low, travelers can cross the river.
The remaining five characters are most commonly found in surnames: 伊 (phonetic for “i”) and 佐 (assistant) both feature the “person” component 
. You can distinguish between these two by finding 左 (left”) in 佐 (“an assistant stands left of the person he is helping”). Look for the “gold” 金 in 鈴 (bell), the “plant”component 
in 藤 (wisteria), and the “letters” 文 topping 斎 (a religious ritual).
Ready to test yourself? Japan’s Top 20 surnames are listed in order of popularity below. Match each name with its meaning in English. Answers are at the end of the column.
No. 1.佐藤 2.鈴木 3.高橋 4.田中 5.渡辺 6.伊藤 7.山本 8.中村 9.小林 10.斎藤 11.加藤 12.吉田 13.山田 14.佐々木 15.山口 16.松本 17.井上 18.木村 19.林 20.清水
a. Mountain-Entrance
b. Add-Wisteria
c. High-Bridge
d. Rice field-Center
e. Grove
f. Pure-Water
g. Lucky-Rice field
h. 2 Assistants-Tree
i. Center-Village
j. Ritual-Wisteria
k. Crossover-Boundary
l. Well-Above
m. Small-Grove
n. Bell-Tree
o. Mountain-Origin
p. Pine tree-Origin
q. Mountain-Rice field
r. Assistant-Wisteria
s. “i”-Wisteria
t. Tree-Village
Today’s 25 kanji can also be recombined to make scores of other popular
surnames, (such as 橋本 Hashimoto, 藤田 Fujita, and 松田 Matsuda). For
a kanji thrill, try thumbing through a Japanese telephone directory--you
will be surprised at how often today’s surname kanji appear, page after
page.
ANSWERS:
1.r-Sato
2.n-Suzuki
3.c-Takahashi
4.d-Tanaka
5.k-Watanabe
6.s-Ito
7.o-Yamamoto
8.i-Nakamura
9.m-Kobayashi
10.j-Saito
11.b-Kato
12.g-Yoshida,
13.q-Yamada
14.h-Sasaki
15.a-Yamaguchi
16.p-Matsumoto
17.l-Inoue
18.t-Kimura
19.e-Hayashi
20.f-Shimizu
Flash quizzes on 516 high-frequency Japanese surnames are here.