Stamp effect in photoshop

I have a logo (you can see it on my forum, link in signature) and I want to add a stamp effect to it in photoshop. To get an idea of what I mean, take a look at this website : http://phpbbfm.net/ they have taken the phpbb logo and added their stamp to it. I want to do a similar thing (only in green and saying forum, hehe).

Any good tutorials I can follow? I've been trying google but I've only found one that actually created something similar to what I mean and that had to be done in a seperate file on a white background, then it I tried to remove the background things screwed up a little.

edit: Heres a link to a tutorial I found, and its what I am looking for only I want it to be square and done on the file http://www.thedesignworld.com/photoshop-tutorials/text-effects/passport-stamp/ I'll have a crack at it but I on't think its going to make something I can put into the file

 

That took me less than 10 seconds to find a tutorial:

http://www.tutorialized.com/tutorial/A-Realistic-Stamp/6856

 

You can make a simple stamp effect with css. Put a 10-15px padding area around your image that contrasts from your bg. Then apply a dashed border around your image the color of your bg.

Example:

padding: 10px;
background: white;
border: 3px dashed grey;

Code (markup):

note: grey is the color of the background of the page in this example.

 

Simple four steps tutorial. Hope This will solve the purpose. In photoshop filters are great help if we know the effect of each and every option. Thank you for the link.

 

Oh, I didn't even look at the tutorial initially. I assumed it was another type of stamp.