Hi kat. The ones he has are small but I use them all the time. When you open one of his textures you simply do a SELECT ALL > EDIT COPY > then minimize the texture > and last EDIT PASTE.
His texture will show small size, so now, just go to menu and do an EDIT > TRANSFORM > SCALE. Now you can make his texture fit your photo and then use the opacity slider for the texture layer to fade or strengthen his texture. Hope this helps.
Just Google "free textures" and you will find thousands for sale. I have never purchased textures, there are so many FREE ones on the net. I will include a link for some of my personal FREE textures. You are welcome to download and use them Well good luck kat and take care - jimmy

FREE TEXTURES - a set on Flickr