Don't say \caption, or \usepackage{caption} and say \caption*{...}, or don't even use \begin{figure}...\end{figure}. I'm not sure what you want. If you want to create a new type float environment, see Section 6.3.1 of TLC or \usepackage{float}. If you want to change show table or figure captions are formatted, try \usepackage{caption}, Section 6.5.1 in TLC. Look up "\@startsection" and "indentation, after headings" in the index of TLC. Basically the amount of indention is controlled by the si