Hi Lazydog,
I guess I would have expected a standard USB A male connector on the keyboard. It's just that I have a suspicious mind and I could not see the connector.
I was going to point out where I had bought a spare OTG cable for my Engage, but then I registered that the Excel has a mini connector. If you have time to wait, I did buy my spare cable from a Chinese website and it is very cheap (US$1.11 postage included). I have done three orders there and they arrived quite quickly considering, a tad under 2 weeks I think. The site is
http://www.buyincoins.com/, however sometimes it runs very slow. Mostly it is fine. I use it for cheap non urgent accessories, like 2 x capacitative stylus for 60p. Why pay £10 in a shop when you can get a cable from China for 65p? After I wrote this, I looked on the site, but sadly they don't seem to have a USB mini OTG, but there are worth looking at just to stock up on cheap accessories. You have to be a little extra careful with mini USB as there are 4 and 5 pin variants. The other place I go for cheap cables (UKbased)
http://etradehouse.com/ doesn't seem to stock anything suitable either. The Ebay item you posted should be fine though, just not as cheap as I would have looked for.
John