Go to a website like this one and do the following:

Find a Smiley you would like to use.
Right click on said smiley.
Go to Properties.
Highlight the Address.
Hit Control-C.
Come Back to PetTalk, and in Post Reply type: [img]
Hit Control-V
Type [/img]

Any questions, ask away!

Theres lots of other pages, too. Go to yahoo or google, and do a search for smileys.

Hope this helps!