I heard you can use a samsung cable but the one I have is to small and you cant put a USB cable into it . SO if anyone has info. on that can you please post here.
Check my sig to the wiki.
I have successfully used a SERIAL Samsung e810 data cable, it had all the pins and it would work for building any cable, here is a link to that on the wiki:
http://wiki.gp2x.org/wiki/SamsungE810Cable
I would personally just build one according to the circuit on the wiki, at this page:
http://wiki.gp2x.org/wiki/USB_Host_BoB_Schematic
If you can't figure it out you need to learn up on Circuits and maybe take a course at a local tech school or community college, it does require certain skills and tools.
Really all it amounts to is 3 things:
1. two data lines with a filtering scheme made of 2 resistors and a capacitor per Line.
2. A ground connection.
3. A +5v voltage source, be creative, use a 9 volt and a 7805 voltage regulator, I have seen that circuit everywhere, even in Popular Science, google for a
DIY 9 volt USB charger, that should get you a power circuit, maybe even pics on how to do it.
To make it very easy just get a powered USB hub (
this comes to mind, being already powered by 4x AAA batteries internally, I found 1000mAh Duracell NiMH AAA's in Walmart for $10) and put the Samsung cord end on it, if it is working crappy get the resistors and capicitors and clean the signal up.
Edit: found the site of the guy who sells em:
http://www.artaylor.co.uk/~richard/gp2x/
Seems so simple I would rather make my own

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Edit: double url qoutes removed.