is it legal to have a friend in florida (not internet) purchase
cigarettes there (much less expensive) and then mail them to me in
mass for personal use?

Assuming that you live in America, I dont see why it would be illegal...

This is NOT legal... notice this excerpt from the PACT(prevent all
cigarette trafficking) act:
"SEC. 3. TREATMENT OF CIGARETTES AND SMOKELESS TOBACCO AS NONMAILABLE MATTER.

Section 1716 of title 18, United States Code, is amended-- 

(1) by redesignating subsections (j) and (k) as subsections (k) and
(l), respectively; and

(2) by inserting after subsection (i) the following new subsection (j): 

`(j)(1) Except as provided in paragraph (2), the transmission in the
mails of any tobacco product, including cigarettes (as that term is
defined in section 1(2) of the Act of October 19, 1949 (15 U.S.C. 375;
commonly referred to as the `Jenkins Act')) and smokeless tobacco (as
that term is defined in section 1(3) of that Act), is prohibited, and
tobacco products are nonmailable and shall not be deposited in or
carried through the mails.

`(2) Paragraph (1) shall apply only to States that are contiguous with
at least one other State of the United States.'.
"

the full act can be found at this URL...
http://www.theorator.com/bills108/s1177.html


Hope this helps.
-CTSDataQA