I have a simple logo (http://www.85angels.com/images/ea85logo.png) and a picture of my friend in a plain gray shirt. How can I effectively apply the logo to this shirt while retaining the texture?

Go to the layers window and try changing the logo layers from "normal" to overlay. If that doesn't give you the effect you want experiment with the other settings in that drop down menu.

http://www.wacom.com/tips/tip.cfm?ID=56&category=Photoshop

Go there great tut on just this.

Cheers

Seamus

http://www.heathrowe.com/tuts/liquify.asp

this one uses the LIQUIFY THANG for the curves - its another take on the same subject!

Try using a displacement map...

http://www.photoshopcafe.com/tutorials/dispmap/dispmap.htm