its easy! you just go to imageshack.com and click upload, select your pic, click host it at the bottom and then select the html thingy ans copy, paste it in your text
if you want to get them of of ZT, you go to your foto album on the game and click the little button that says something like export to computer or so and i think it appears on a website, from there, just save them!
hope that helps, if not just do a search on the forums, there is a lot of topics on this subject!
Like my Signature? PM TigerGirl for one!