Ok, in Quacker's method there are a few assumptions. Firstly, you have to save the image you want somewhere on your computer. If you can manage that, we are half way there. Secondly, you need to use Tinypic.
1) Access Tinypic site:
http://tinypic.com/
2) Select "Image" - click on "Browse" and select the desired picture from your folder you saved the pictures in,
3) Hit "Upload now",
4) Enter the "anti-bot" spam code. It's self explanatory,
5) Get to the final screen and you have four boxes containing links to that image. Click on the one named as: "IMG code for forum and message boards" and you should highlight that text.
6) Hit CTRL + C (copied) and then open up the post on the thread you want the picture on and hit CTRL + V and your post should get a line of text.
7) Hit "Post" and your line of text should metamorphisie into a picture.
Hmm I don't have an iPad so these instructions are not specific to that device. They seem to work on any type of computer. Maybe give it a try and see how it goes? Hope it works.
EDIT: I guess you won't want to save a picture on your iPad - due to space issues? In that case right click the picture (or however you access the menu) - select "View Image". At the top of your browser should be the address for that image - Copy it (CTRL + C). Go back to Tiny Pic, but instead of selecting "image" use "URL". Paste said URL into the URL box and follow the rest of my intructions I made earlier. Should have the same result.