[Is there a texture I can use to put holes in a prim for windows?]

Also, all textures should be saved as either .tga (targa) or .png files and it costs 10 Lindens to upload each texture file.

[Is there a texture I can use to put holes in a prim for windows?]

Yes, it's called an alpha texture. These are textures that you can make in Photoshop and Gimp. If you have either one, it's a really simple process. If you don't have either, you can get Gimp for free at www.gimp.org. You can also find out how to make alpha textures and everything else Second Life related on Youtube. It's a great resource for tutorials. Once you have either Photoshop or Gimp, you can open a new document from the file tab in the upper left part of the screen. When the new document box pops up, you can choose to make your entire background transparent, or you can make it white and erase the parts that you want to be transparent and decorate the rest. If this didn't help, check out "How to make alpha textures" on Youtube.