In Lion, youYou can open man pages in a single, scrollable window from Terminal's Help menu. Just type the command into the search field in the Help menu, then click the command in the search results to open its man page. It may occasionally take a few seconds for the command to appear in the search results.
If you're not using Lion yet, youYou can also find most man pages online, with Apple-specific man pages found on apple's developer library. I generally google with apple man [command] replacing [command] with the actual command. One nice thing about this method is you can easily bookmark man pages you use frequently.