I have read somewhere there's a tweak to get more pages. One option is to install the 5 icons across, so that would you at least about 50-55 additional icons.

11 pages is the max for Iphone 3GS and perhaps for OS3.12 (its stated on Apple's website). Anything extra that yfou install, you can still run it by searching first and typing the app name in the search function.