Try a search in the national semiconductors' site. Other manufacturers like Maxim and Linear Techn. have a good range of ics.
Some IC numbers are LM3410, MAX668, LT1070, LT1071...
I use the LM3410 and it is very nice, it can deliver 350 mA without any problem (even more mA). Find the circuit diagram from the datasheets.
Also the LT107X series is very simple to use.
Here you can find the diagram of my design.
4-6V input and 9 to 17V output, constant current, (with R3 0.5Ohms it gives 380mA).
Output current is I=190mV/R3.
http://rapidshare.com/files/113360888/5V_to_9-17V_constant_current_converter_for_LED.jpgRegards
P.