The formats of entries in the table of contents (TOC) are
controlled by a number of internal commands (discussed in section 2.3
of The LaTeX Companion. The commands
\@dotsep control the space
for page numbers, the indentation of the right-hand margin, and the
separation of the dots in the dotted leaders, respectively. The
series of commands named
_xxx_ is the name of
a sectional heading (such as
controls the layout of the corresponding heading, including the space
for section numbers. All these internal commands may be individually
redefined to give the effect that you want.
All that work may be avoided, using the package
which provides a set of user-level commands that may be used to change
the TOC formatting. Since exactly the same mechanisms are used
for the List of Figures and List of Tables, the layout of these sections
may be controlled in the same way.
etoc package offers similar flexibility,
together with multicolumn tables of contents and boxes around tables
(and the like).
KOMA-Script classes provides
an optional variant structure for the table of contents, and calculates
the space needed for the numbers automatically.
memoir class includes the functionality