Create Gradient Text Fill

Ok, so as I mentioned above, I don't have my computer, so I'm winging it. To get your rgb numbers, you should be able to click on the foreground color square in the tool bar. If you enter a hex value, it should show what the rgb values are.

To add a gradient overlay to the text, double click on the layer in the layer panel. The layer effects panel should pop up. On the left side, there should be an option for gradient fill or overlay. Use that and enter you color values. 

So do you want the text to have a gradient? How is the image of the cards used: also part of the text, the background, or is the gradient to go over the markings on the cards?

I'll try to explain the process better, but I'm away from my computer for several days, and have to rely on my memory, which is a bit spotty these days.

You can type your text, then either use layer styles to add a gradient fill, or add a gradient fill adjustment layer above the type layer, then clip it to the type,  by pressing alt/opt and clicking between the two layers, in the layer panel. As far as hex vs rgb, they're both relatively to your system, you could look in the normal color picker and enter the hex code, then see what rgb value you get, but don't expect accuracy.