Relative Frequencies of Letters in General English Plain text
From Cryptographical Mathematics, by Robert Edward Lewand

 Letter Frequency Letter Frequency a 0.08167 n 0.06749 b 0.01492 o 0.07507 c 0.02782 p 0.01929 d 0.04253 q 0.00095 e 0.12702 r 0.05987 f 0.02228 s 0.06327 g 0.02015 t 0.09056 h 0.06094 u 0.02758 i 0.06966 v 0.00978 j 0.00153 w 0.02360 k 0.00772 x 0.00150 l 0.04025 y 0.01974 m 0.02406 z 0.00074

Tom's Letter Frequencies (in order)

By analyzing roughly 15000 characters, or roughly 2700 words from three separate sources, Tom came up with the statistics below. The three sources were:
• The license agreement from Sun for JDK 1.2.1.
• The teaching philosophy of a computer science professor from a liberal arts college in Minnesota.
• A letter of recommendation for a national competition for innovative uses of technology in collegiate teaching.
General Letter Frequencies
 e 0.124167 t 0.0969225 a 0.0820011 i 0.0768052 n 0.0764055 o 0.0714095 s 0.0706768 r 0.0668132 l 0.0448308 d 0.0363709 h 0.0350386 c 0.0344391 u 0.028777
 m 0.0281775 f 0.0235145 p 0.0203171 y 0.0189182 g 0.0181188 w 0.0135225 v 0.0124567 b 0.0106581 k 0.00393019 x 0.00219824 j 0.0019984 q 0.0009325 z 0.000599

The top ten letters with frequencies, which occur at the beginning of words:

 Letter t a i s o c m f p w Freq 0.1594 0.155 0.0823 0.0775 0.0712 0.0597 0.0426 0.0408 0.040 0.0382

The top ten letters with frequencies, which occur at the end of words:

 Letter e s d t n y r o l f Freq 0.1917 0.1435 0.0923 0.0864 0.0786 0.0730 0.0693 0.0467 0.0456 0.0408

The most common digrams (in order):
th, he, in, en, nt, re, er, an, ti, es, on, at, se, nd, or, ar, al, te, co, de, to, ra, et, ed, it, sa, em, ro.

The most common trigrams (in order):
the, and, tha, ent, ing, ion, tio, for, nde, has, nce, edt, tis, oft, sth, men